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- Мильштейн Александр Ильич

# Мильштейн Александр Ильич

доктор физико-математических наук, профессор- Article. Baier V. N., Milstein A. I. To the theory of a free-electron laser // Physics Letters, Section A: General, Atomic and Solid State Physics. Elsevier BV. Netherlands. - P.319-322. - ISSN 03759601. The interaction of an electron beam, moving inside a magnetic lattice, with an electromagnetic wave is considered. It is shown that under certain conditions generation (amplification) of coherent electromagnetic radiation occurs. The gain is calculated. © 1978.
- Article. Baier V. N., Milstein A. I. Radiative effects in a plane wave moving along a magnetic field // Radiative effects are considered when a scalar particle interacts with the field of an intense plane wave of a general type propagating along a magnetic field. Within the framework of operator technique the mass operator of a particle is calculated. A detailed analysis in the case of a circularly polarised monochromatic wave is carried out. The behavior of particles in the vicinity of the cyclotron resonance is analysed.
- Article. Mil'shtein A. I., Strakhovenko V. M. The O(2.1) algebra and the electron green function in a Coulomb field // Physics Letters, Section A: General, Atomic and Solid State Physics. Elsevier BV. Netherlands. - P.447-450. - ISSN 03759601. An integral representation for the Green function of a charged particle moving in a Coulomb field is obtained, with the help of the O(2.1) algebra, in a form convenient for applications. © 1982.
- Article. Mil'shtein A. I., Strakhovenko V. M. Electron green function and vacuum polarization in a Coulomb field // Physics Letters, Section A: General, Atomic and Solid State Physics. Elsevier BV. Netherlands. - P.381-384. - ISSN 03759601. An explicit expression for the renormalized charge density induced in the presence of a Coulomb field is derived both in momentum and coordinate space, by taking advantage of an integral representation for the electron Green function obtained earlier by the authors. © 1982.
- Article. Mil'shtein A. I., Strakhovenko V. M. Quasiclassical approach to the high-energy Delbrück scattering // Physics Letters, Section A: General, Atomic and Solid State Physics. Elsevier BV. Netherlands. - P.135-138. - ISSN 03759601. A quasiclassical approach intended for description of the quantum electrodynamic processes in the Coulomb field at high energies is developed. An expression for the high-energy Delbrück scattering amplitude is derived in a simple form, thereby allowing to define the dependence of the total cross section on the charge of the Coulomb centre. © 1983.
- Article. Mil'shtein A. I., Pinelis Yu F. Properties of the photon polarization operator in a long-wave vacuum field in QCD // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.235-240. - ISSN 03702693. The analytical properties of the photon polarization operator Παβ(q) are considered using the Lorentz-invariant averaging over the covariantly constant field Gων orientation in QCD. It is shown that the usual operator expansion is valid below the threshold. It turns out that Παβ(q) has no cut in the complex plane q2. This means quark confinement in this field. © 1984.
- Article. Baier V. N., Mil'shtein A. I. EFFECTIVE NARROWING OF THE SPECTRAL DISTRIBUTION AT MULTIPLE PASSAGE OF PHOTONS THROUGH A FREE ELECTRON LASER (FEL). // IEEE Journal of Quantum Electronics. Institute of Electrical and Electronics Engineers. United States. - P.1023-1025. - ISSN 00189197. It is shown that the spectral density at the center of the radiation line is effectively increased if the gain of a free-electron laser (FEL) is on the order of unity and when the signal repeatedly passes through an optical cavity because of the nonlinear interaction between harmonics. The action of a FEL is studied for the case of a nonmonoenergetic electron beam.
- Article. Mil'shtein A. I., Pinelis Yu F. Non-Abelian constant fields and the vacuum expectation values // Zeitschrift f�r Physik C-Particles and Fields. Springer Verlag. Germany. - P.461-467. - ISSN 01709739. The nonperturbative effects in SUc(2) gauge theory, which are due to the non-Abelian constant fields, are analysed. The nonrelativistic polarization operator II(E) is obtained in these fields. The operator expansion is not applicable if the nonperturbative corrections are larger than the relativistic corrections. At high energies, it is possible to make the analytic continuation of the derived polarization operator from the under-threshold region to the physical by means of the continuation of each operator expansion term individually. The Borel transform II(τ) of the nonrelativistic polarization operator is sensitive not only to the gluon condensate value but also to the vacuum field structure. The non-Abelian constant fields don't lead to the spontaneous chiral symmetry breaking but generate the nonperturbative quark mass renormalization. © 1985 Springer-Verlag.
- Article. Baier V. N., Milstein A. I. Electromagnetic-wave amplification by an electron beam in aligned single crystals // Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. Elsevier BV. Netherlands. - P.25-29. - ISSN 0168583X. A consistent analysis has been made of the amplification of an electromagnetic wave during its interaction with electrons and positrons moving in planar channels of a single crystal. The main effects: dechanneling, unharmonism in transverse motion and radiation losses of energy, have been taken into account. We have concluded that even for the high beam density (n = 1014 cm-3) the gain appears to be very low: G ≈ 10-12. © 1986.
- Article. Milstein A. I. On the green function calculation for heavy quarkonium potential models // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.141-145. - ISSN 03702693. A new method for numerical calculation of the Green functions of the Schrödinger equation is proposed in the case of spherically symmetric potentials. This method can be applied to the potentials describing heavy quarkonium as well as to other problems of quantum mechanics. The case of the Coulomb potential with a running coupling constant is considered in detail. © 1986.
- Article. Baier V. N., Milstein A. I., Shaisultanov R. Zh Photon splitting in a strong electromagnetic field and the possibility of its observation in single crystals // Physics Letters, Section A: General, Atomic and Solid State Physics. Elsevier BV. Netherlands. - P.255-258. - ISSN 03759601. The process of photon splitting in the field of the axes in single crystals is considered. It turns out that the observation of the process is possible only within the maximum probability region. This maximum is achieved at a photon energy of a few hundred GeV. The consideration is based on the amplitudes obtained in a quasiclassical approximation. © 1987.
- Article. Milstein A. I. A new method for calculation of the green functions of the Schrödinger equation // Physics Letters, Section A: General, Atomic and Solid State Physics. Elsevier BV. Netherlands. - P.1-5. - ISSN 03759601. A new method for calculation of the Green functions of the Schrödinger equation is proposed. It can be applied to different problems of quantum mechanics, e.g. to the problem of N particles interacting by spherically symmetric potentials. This method gives an essential advantage in the numerical calculations. © 1987.
- Article. Milstein A. I., Shaisultanov R. Z. High-energy Delbruck scattering at large angles // Journal of Physics A: Mathematical and General. Institute of Physics Publishing. United Kingdom. - P.2941-2952. - ISSN 03054470. - EISSN 13616447. An expression for the high-energy Delbruck amplitude at large scattering angles is derived. This expression is exact in the parameter Z alpha . The consideration is based on the use of the relativistic electron Green's function in a Coulomb field.
- Article. Milstein A. I. Radiative electron-ion recombination // Physics Letters, Section A: General, Atomic and Solid State Physics. Elsevier BV. Netherlands. - P.52-54. - ISSN 03759601. The process of the radiative recombination of a nonrelativistic electron with a hydrogen-like ion is considered. A simple expression is derived for the total cross section of the process using the analytic properties of the electron Green function in a Coulomb field. The dipole approximation is used. © 1989.
- Article. Milstein A. I. Operator approach to the calculation of nonrelativistic amplitudes in a Coulomb field // Physics Letters, Section A: General, Atomic and Solid State Physics. Elsevier BV. Netherlands. - P.335-339. - ISSN 03759601. A new method for the calculation of the nonrelativistic amplitudes in a Coulomb field is proposed. The method is based on an operator representation of the Green function for a charged particle with a subsequent disentanglement of operator expressions. The dynamical algebra O (4,2) of the hydrogen atom is used. The calculation of the bremsstrahlung cross section is performed. © 1989.
- Article. Milstein A. I., Yelkhovsky A. S. Vacuum polarization and magnetic moment of a heavy nucleus // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.11-15. - ISSN 03702693. The contribution of the vacuum polarization to the magnetic moment of a heavy nucleus is considered. The leading term is obtained in Zα, using the electron Green's function in the Coulomb field. This term contains a large logarithm of the ratio λe R, where R is the nuclear radius. © 1989.
- Article. Milstein A. I., Yelkhovsky A. S. Vacuum polarization and the quadrupole moment of a heavy nucleus // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.184-188. - ISSN 03702693. The contribution of the vacuum polarization to the quadrupole moment of a heavy nucleus is considered. The leading term is obtained exactly in Zα, using the electron Green function in the Coulomb field. This term contains the large logarithm of the ratio λ R, where R is the radius of the nucleus. The spatial distributions of the induced charge and potential are discussed also. © 1990.
- Article. Milstein A. I., Rullhusen P., Schumacher M. High-energy Delbrück scattering from a heavy nucleus at large angles // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.481-484. - ISSN 03702693. High-energy Delbrück scattering amplitudes are studied to all orders in the parameter Zα. Coulomb corrections are found to decrease the amplitudes substantially. The comparison of our theoretical predictions with recent experimental results leads to good agreement. © 1990.
- Review. Falkenberg H., Hünger A., Rullhusen P., Schumacher M., Milstein A. I., Mork K. Amplitudes for Delbrück scattering // Atomic Data and Nuclear Data Tables. Academic Press. United States. - P.1-27. - ISSN 0092640X. - EISSN 10902090. Delbrück scattering amplitudes are calculated in the lowest-order Born approximation, in the small-angle high-energy approximation, and in the large-angle high-energy approximation. Interpolation procedures suitable for generating state-of-the-art Delbrück scattering amplitudes for any angular and energy interval are described. © 1992.
- Article. Baumann A., Rullhusen P., Rose K. W., Ludwid M., Schumacher M., Milstein A. I., Henneberg J. M., Wieloch-Laufenberg N., Ziegler B. Delbrück scattering of 30-100 MeV photons by Pb through angles of 15°-30° // Nuclear Physics A. Elsevier BV. Netherlands. - P.87-108. - ISSN 03759474. Elastic (Compton) scattering of 30-100 MeV protons by Pb through angles of 15°-30° is measured using the MPI tagged-photon facility at MAMI A. The data are discussed in terms of three different approaches to Delbrück scattering, viz. the lowest-order Born approximation, the small-angle high-energy approximation, and the large-angle high-energy approximation. The latter method which is investigated in detail for the first time, leads to a good agreement with experiment at Θ = 20° but to some disagreement at Θ = 15°. © 1992.
- Article. Khriplovich I. B., Milstein A. I., Yelkhovsky A. S. Corrections of O(α6 log α) in the two-body QED problem // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.237-242. - ISSN 03702693. The corrections in the QED two-body problem are calculated in perturbation theory for the non-relativistic Schrödinger equation. Perturbation operators are derived by computing on-mass-shell Feynman diagrams in a non-covariant approach. For positronium, the calculated logarithmic corrections does not vanish only in n3S1 states and equals 5 24mα6log(l|γ)|n3. © 1992.
- Article. Drake G. W F, Khriplovich I. B., Milstein A. I., Yelkhovsky A. S. Energy corrections of order mc2α6lnα in helium // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.R15-R17. - ISSN 10941622. Quantum-electrodynamic corrections of O(mc2α6lnα) to the electron-electron interaction in helium are evaluated for several states. The additional energy shift, which is an order of α smaller than the leading Araki-Sucher terms, raises the predicted energy of the 1s2s 1S0 state by 2.49 MHz to -960 332 039.43(18) MHz relative to He+(1s). The new value significantly alters the comparison with recent high-precision experiments. © 1993 The American Physical Society.
- Article. Khriplovich I. B., Milstein A. I., Yelkhovsky A. S. Order α4R corrections to the fine-structure splitting of positronium P levels // Physical Review Letters. American Physical Society. United States. - P.4323-4325. - ISSN 00319007. - EISSN 10797114. The order α4R corrections to the fine-structure splitting of positronium P levels are found. The calculation is reduced to the ordinary perturbation theory for the nonrelativistic Schrödinger equation. The perturbation operators have the Breit-type structure and are obtained by calculating on-mass-shell diagrams. The correction found is -0.64 MHz for the 23P0-21P1 energy splitting. © 1993 The American Physical Society.
- Article. Khriplovich I. B., Milstein A. I., Yelkhovsky A. S. Logarithmic corrections in the two-body qed problem // Physica Scripta. Royal Swedish Academy of Sciences. Sweden. - P.252-260. - ISSN 00318949. The logarithmic part of the Lamb shift, the contribution of the relative order a3log (1/a) to the atomic state energy, is related to the usual infrared divergence. This fact allows one to calculate easily such corrections in positronium, and derive the recoil and electron-electron terms in the Lamb- shift Hamiltonian in many-electron atoms. Logarithmic energy corrections of the next order, a4 log (1/a), are of a different, relativistic nature. Their calculation is reduced to the ordinary perturbation theory for the nonrelativistic Schrodinger equation. The perturbation operators have the Breittype structure and are found by the calculation of on-mass-shell diagrams. For positronium, the calculated log-arithmic correction survives only in n3Sj states and constitutes ¿ma6 log (l/a)/n3. Logarithmic corrections of the relative order a2 log (1/a) to the positronium decay rate are also of the relativistic origin and can be easily computed within the same approach. Arguments are presented in favour of a large numerical factor in the (a/rc)2 correction to the positronium decay rate. © 1993 IOP Publishing Ltd.
- Article. Fell R. N., Khriplovich I. B., Milstein A. I., Yelkhovsky A. S. On the recoil corrections in hydrogen // Physics Letters, Section A: General, Atomic and Solid State Physics. Elsevier BV. Netherlands. - P.172-174. - ISSN 03759601. We demonstrate the absence of logarithmic recoil corrections of relative order (m/M) α4 log α to the hydrogen spectrum. © 1993.
- Erratum. Drake G. W F, Khriplovich I. B., Milstein A. I., Yelkhovsky A. S. Erratum: Energy corrections of order mc2α6 In α in helium (Physical Review A (1993) 48, 6 (4804) // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.4804. - ISSN 10941622.
- Review. Milstein A. I., Schumacher M. Present status of Delbrück scattering // Physics Reports. Elsevier BV. Netherlands. - P.183-214. - ISSN 03701573. Recent developments in the theory of Delbrück scattering and experimental results obtained after the latest review article of 1975 are discussed. Theoretical predictions and experimental data are in a general agreement at energies below 12 MeV, except for the Coulomb correction effect which remains to be calculated. Information on the relative size of the Coulomb correction effect compared to the lowest-order Born approximation is extracted from the experimental data. In the 20 to 100 MeV energy range Delbrück scattering has also been clearly identified, but furthergoing studies are desirable both on the experimental and theoretical sides. In the high-energy range above 1 GeV the high-energy small-angle approximation leads to a satisfactory agreement with experiment. Attention is paid to the interference of Delbrück scattering with atomic Rayleigh scattering and with scattering through the excitation of different modes of nuclear excitation. © 1994.
- Article. Lee R. N., Milstein A. I. Finite nuclear size and vacuum polarization in heavy atoms // Physics Letters, Section A: General, Atomic and Solid State Physics. Elsevier BV. Netherlands. - P.72-79. - ISSN 03759601. The effect of finite nuclear size R on the induced-charge density is discussed. A simple analytical expression for the corresponding variation δρ{variant}fs (r) is obtained at distances much larger than R. The expression is exact with respect to the nuclear charge. The dependence of δρ{variant}fs (r) on the charge density distribution inside the nucleus is investigated. The consideration is based on the use of the electron Green function in the Coulomb field. © 1994.
- Article. L'vov A. I., Milstein A. I. Relativistic oscillator model and Delbrück scattering // Physics Letters, Section A: General, Atomic and Solid State Physics. Elsevier BV. Netherlands. - P.185-191. - ISSN 03759601. Elastic scattering of photons in a Lorentz-scalar potential via virtual spin-zero particle-antiparticle pairs ("Delbrück scattering") is considered. An analytic expression for the Delbrück amplitude is found exactly in the case of an oscillator potential. General properties of the amplitude and its asymptotics are discussed. © 1994.
- Article. Schumacher M., Milstein A. I., Falkenberg H., Fuhrberg K., Glebe T., Häger D., Hütt M. The enhancement of giant-dipole strength and its consequences for the effective mass of the nucleon and the electromagnetic polarizabilities and quadrupole sum-rule of the nucleus // Nuclear Physics A. Elsevier BV. Netherlands. - P.603-625. - ISSN 03759474. Using recent experimental results on Compton scattering by 208Pb at energies below pion threshold we explore the effects of enhancement due to mesonic currents and isovector vibrations on the giant resonances of nuclei. Quantitative information is given for the enhancements of the electric polarizability, the diamagnetic susceptibility and the energy-weighted quadrupole sum rule. It is shown that the average of results available from different laboratories on the "nonretarded" enhancement constant KGDR in the A = 197-209 mass range favours an effective nucleon mass of m* m = 3 4. Some new results for the amplitude of Compton scattering by the giant resonances of nuclei are presented which allow a treatment of the retardation problem in a zero-order approximation. © 1994.
- Article. Eides M. I., Khriplovich I. B., Milstein A. I. Radiative corrections to P-levels in the two-body QED problem // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.275-277. - ISSN 03702693. The physical origin of the mα5 radiative corrections to P-levels in the two-body QED problem is elucidated. Then we demonstrate that the next order, mα6, corrections to those levels are due to the anomalous magnetic moment only. © 1994.
- Article. Lee R. N., Milstein A. I. Quasiclassical Green function and Delbrück scattering in a screened Coulomb field // Physics Letters, Section A: General, Atomic and Solid State Physics. Elsevier BV. Netherlands. - P.217-224. - ISSN 03759601. A simple integral representation is derived for the quasiclassical Green function of the Dirac equation in an arbitrary spherically symmetric decreasing external field. The consideration is based on the use of the quasiclassical radial wave functions with the main contribution of large angular momenta taken into account. The Green function obtained is applied to the calculation of the Delbrück scattering amplitudes in a screened Coulomb field. © 1995.
- Article. Baier V. N., Milstein A. I. Azimuthal asymmetry in processes of nonlinear QED for linearly polarized photon // Zeitschrift f�r Physik C-Particles and Fields. Springer Verlag. Germany. - P.427-430. - ISSN 01709739. Cross sections of nonlinear QED processes (photon-photon scattering, photon splitting in a Coulomb field, and Delbrück scattering) are considered for linearly polarized initial photon. The cross sections have sizeable azimuthal asymmetry. © 1996 Springer-Verlag.
- Article. Khriplovich I. B., Milstein A. I., Petrosyan S. S. Nuclear structure corrections to deuterium hyperfine splitting // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.13-17. - ISSN 03702693. The low-energy theorem for the forward Compton scattering is generalized to the case of an arbitrary target spin. The generalization is used to calculate the corresponding contribution to the deuterium hyperfine structure. The nuclear-structure corrections are quite essential in this case due to the deuteron large size. Within their estimated accuracy, corrections of this type calculated here remove the discrepancy between the theoretical and experimental values of the deuterium hyperfine splitting.
- Article. Khriplovich I. B., Milstein A. I., Sen'kov R. A. Nature of the Darwin term and (Zα)4m3/M2 contribution to the Lamb shift for an arbitrary spin of the nucleus // Physics Letters, Section A: General, Atomic and Solid State Physics. Elsevier BV. Netherlands. - P.370-374. - ISSN 03759601. The contact Darwin term is demonstrated to be of the same origin as the spin-orbit interaction. The (Zα)4m3/M2 correction to the Lamb shift, generated by the Darwin term, is found for an arbitrary nonvanishing spin of the nucleus, both half-integer and integer. There is also a contribution of the same nature to the nuclear quadrupole moment.
- Article. Hütt M. Th, Milstein A. I. Mesonic contribution to the Compton scattering amplitude for heavy nuclei // Nuclear Physics A. Elsevier BV. Netherlands. - P.391-410. - ISSN 03759474. The contribution of mesonic exchange currents to nuclear Compton scattering is investigated within the framework of a Fermi gas model of nuclear matter in the non-relativistic limit. The additional interaction between the nucleons is accounted for by including two- and three-body diagrams. As a test of this model, the enhancement constant κ is calculated. The full correlators for the central and tensor parts of the nucleon-nucleon interaction due to pion exchange are obtained and the energy dependence of the amplitude is investigated. The contribution of the Δ-excitation to the mesonic part of the Compton amplitude is calculated explicitly using an effective Hamiltonian in the static limit.
- Article. Baier V. N., Milstein A. I., Zh Shaisultanov R. Photon splitting in a very strong magnetic field // Physical Review Letters. American Physical Society. United States. - P.1691-1694. - ISSN 00319007. - EISSN 10797114. Photon splitting in a very strong magnetic field is analyzed for energy ω < 2m. The amplitude obtained on the base of the operator-diagram technique is used. It is shown that in a magnetic field much higher than a critical one the splitting amplitude is independent of the field. Our calculation is in good agreement with previous results of Adler and in strong contradiction with a recent paper by Mentzel et al.
- Article. Khriplovich I. B., Milstein A. I., Sen'kov R. A. Nature of the Darwin term and (Zα)4m3/M2 contribution to the Lamb shift for an arbitrary spin of the nucleus // Journal of Experimental and Theoretical Physics. Maik Nauka/Interperiodica Publishing. Russian Federation. - P.1054-1057. - ISSN 10637761. - EISSN 10906509. The contact Darwin term is demonstrated to be of the same origin as the spin-orbit interaction. The (Zα)4m3/M2 correction for the Lamb shift, generated by the Darwin term is found for an arbitrary nonvanishing spin of the nucleus, both half-integer and integer. There is also a contribution of the same nature to the nuclear quadrupole moment. © 1997 American Institute of Physics.
- Article. Hütt M. Th, Milstein A. I., Schumacher M. Model for analytical calculation of nuclear photoabsorption at intermediate energies // Nuclear Physics A. Elsevier BV. Netherlands. - P.483-497. - ISSN 03759474. The universal curve σ/A of nuclear photoabsorption is investigated within a Fermi gas model of nuclear matter. An energy range from pion threshold up to 400 MeV is considered. The interactions between nucleon, pion, Δ-isobar and photon are considered in the non-relativistic approximation with corrections of the order 1/M taken into account with respect to proton mass. Analytical expressions are obtained, in which the influence of nuclear correlations and two-nucleon contributions is studied explicitly. The contributions of real and virtual pions are found to be sufficient to obtain agreement with experimental data in this energy range. An extension of the model calculation to nucleon knock-out reactions is discussed. © 1997 Elsevier Science B.V.
- Article. Baǐer V. N., Mil'Shteǐn A. I., Zh Shaǐsultanov R. Photon splitting in an ultrastrong magnetic field // Journal of Experimental and Theoretical Physics. Maik Nauka/Interperiodica Publishing. Russian Federation. - P.29-34. - ISSN 10637761. - EISSN 10906509. We analyze the splitting of a photon with energy ω > below the e+e- pair-production threshold in an ultrastrong magnetic field. We use the amplitudes found by employing the operator diagrammatic technique. In a field considerably above the critical values the process amplitudes become independent of the field strength. A study of the polarization operator of a photon in an external field of arbitrary strength in the energy range considered in the present investigation shows that there is only one set of polarizations of the initial and final photons for which the splitting amplitude is nonzero. ©7997 American Institute of Physics.
- Article. Khriplovich I. B., Milstein A. I., Sen'ko R. A. Nature of the Darwin term and (Zα)4m3/M2 contribution to the lamb shift for an arbitrary spin of the nucleus // Zhurnal Eksperimental'noi i Teroreticheskoi Fiziki. Izdatel'stvo Nauka. Russian Federation. - P.1935-1941. - ISSN 00444510. The contact Darwin term is demonstrated to be of the same origin as the spin-orbit interaction. The (Zα)4m3/M2 correction for the Lamb shift, which is generated by the Darwin term, is found for an arbitrary nonvanishing spin of the nucleus, both half-integer and integer. There is also a contribution of the same nature to the nuclear quadrupole moment.
- Article. Hütt M. Th, Milstein A. I. Meson-induced correlations of nucleons in nuclear Compton scattering // Physical Review C - Nuclear Physics. American Physical Society. United States. - P.305-311. - ISSN 05562813. - EISSN 1089490X. The nonresonant (seagull) contribution to the nuclear Compton amplitude at low energies is strongly influenced by nucleon correlations arising from meson exchange. We study this problem in a modified Fermi gas model, where nuclear correlation functions are obtained with the help of perturbation theory. The dependence of the mesonic seagull amplitude on the nuclear radius is investigated and the influence of a realistic nuclear density on this amplitude is discussed. We found that different form factors appear for the static part (proportional to the enhancement constant κ) of the mesonic seagull amplitude and for the parts, which contain the contribution from electromagnetic polarizabilities.
- Article. Lee R. N., Milstein A. I., Strakhovenko V. M. High-energy photon splitting on heavy atoms // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.2325-2338. - ISSN 10941622. The helicity amplitudes of high-energy photon splitting in an external Coulomb field are obtained exactly in the parameter Zα. The consideration is based on the quasiclassical approach, valid for small angles between all photon momenta. A new representation of the quasiclassical electron Green function is exploited. General expressions obtained are analyzed in detail when the transverse momenta of both final photons are much larger than the electron mass. It is shown that, at Zα∼1, Coulomb corrections essentially change the cross section as compared to the Born approximation. Screened and unscreened potentials are considered.
- Article. Lee R. N., Milstein A. I., Strakhovenko V. M. Cross section of high-energy photon splitting in the electric fields of heavy atoms // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.1757-1764. - ISSN 10941622. Various differential cross sections of high-energy photon splitting in the electric fields of heavy atoms are calculated exactly in the parameter Zα. The consideration is based on the quasiclassical approach applicable for small angles between all photon momenta. The expressions obtained are valid for arbitrary transverse momenta of final photons. The detailed investigation of the process is performed taking into account the effect of screening. The exact cross section turns out to be noticeably smaller than the result obtained in the Born approximation.
- Article. Akhmadaliev Sh Zh, Kezerashvili G. Ya, Klimenko S. G., Malyshev V. M., Maslennikov A. L., Milov A. M., Milstein A. I., Muchnoi N. Yu, Naumenkov A. I., Panin V. S., Peleganchuk S. V., Popov V. G., Pospelov G. E., Protopopov I. Ya, Romanov L. V., Shamov A. G., Shatilov D. N., Simonov E. A., Tikhonov Yu A. Delbrück scattering at energies of 140-450 MeV // Physical Review C - Nuclear Physics. American Physical Society. United States. - P.2844-2850. - ISSN 05562813. - EISSN 1089490X. The differential cross section of Delbrück scattering is measured on a bismuth germanate (Bi4Ge3O12) target at photon energies 140-450 MeV and scattering angles 2.6-16.6 mrad. A good agreement with the theoretical results, obtained exactly in a Coulomb field, is found.
- Article. Li R. N., Mil'shteǐn A. I., Strakhovenko V. M. Simple analytical representation for Delbrück scattering amplitudes at high energies // Journal of Experimental and Theoretical Physics. Maik Nauka/Interperiodica Publishing. Russian Federation. - P.41-44. - ISSN 10637761. - EISSN 10906509. We use a new representation for the semiclassical Green's function of the Dirac equation in the Coulomb field to find an exact (in the parameter Za) expression for the amplitudes of small-angle Delbrück scattering of high-energy photons. The values of these amplitudes agree with those obtained in earlier calculations, but the structure of the expressions is much simpler than that of previously known representations, which makes numerical calculations much easier. © 1999 American Institute of Physics.
- Article. Akhmetshin R. R., Anashkin E. V., Arpagaus M., Aulchenko V. M., Banzarov V. Sh, Barkov L. M., Bashtovoy N. S., Bondar A. E., Bondarev D. V., Bragin A. V., Chernyak D. V., Chertovskikh A. G., Dvoretsky A. S., Eidelman S. I., Fedotovitch G. V., Gabyshev N. I., Grebeniuk A. A., Grigoriev D. N., Ivanov P. M., Karpov S. V., Kazanin V. F., Khazin B. I., Koop I. A., Korostelev M. S., Krokovny P. P., Kurdadze L. M., Kuzmin A. S., Logashenko I. B., Lukin P. A., Lysenko A. P., Mikhailov K. Yu, Milstein A. I., Nesterenko I. N., Okhapkin V. S., Otboev A. V., Perevedentsev E. A., Polunin A. A., Popov A. S., Purlatz T. A., Root N. I., Ruban A. A., Ryskulov N. M., Shamov A. G., Shatunov Yu M., Shekhtman A. I., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Skrinsky A. N., Smakhtin V. P., Snopkov I. G., Solodov E. P., Stepanov P. Yu, Sukhanov A. I., Titov V. M., Valishev A. A., Yudin Yu V., Zverev S. G., Thompson J. A., Hughes V. W. a1(1260)π dominance in the process e+e- → 4π at energies 1.05-1.38 GeV // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.392-402. - ISSN 03702693. The 5.8 pb-1 of data collected by the CMD-2 Collaboration in the energy range 1.05-1.38 GeV have been used to study energy dependence of the processes e+e- → π+π-2π0 and e+e- → 2π+2π-. Analysis of the differential distributions demonstrates the dominance of the a1(1260)π and ωπ intermediate states. Upper limits for the contributions of other possible states are also obtained. © 1999 Published by Elsevier Science B.V. All rights reserved.
- Article. Bondar A. E., Eidelman S. I., Milstein A. I., Root N. I. On the role of the a1(1260) meson in τ → 4πντ decay // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.403-407. - ISSN 03702693. It is shown that a simple model successfully describing experimental data on the process e+e-→ 4π can also qualitatively account for the data of CLEOII and ALEPH obtained recently in the decay τ → 4πντ. The model is based on the assumption of the a1(1260)π and ωπ dominance as intermediate states. Our observation is in contrast with the claim by ARGUS that the ρ-meson signal in the τ → 4πντ decay can not be explained by the a1(1260)π intermediate state. © 1999 Published by Elsevier Science B.V. All rights reserved.
- Article. Khriplovich I. B., Milstein A. I., Sen'kov R. A. Nature of the Darwin term and (Zα) 4m 3/M 2 contribution to the Lamb shift for an arbitrary spin of the nucleus // Surveys in High Energy Physics. Taylor & Francis. United Kingdom. - P.175-184. - ISSN 01422413. The contact Darwin term is demonstrated to be of the same origin as the spin-orbit interaction. The (Zα) 4m 3/M 2 correction to the Lamb shift, generated by the Darwin term, is found for an arbitrary nonvanishing spin of the nucleus, both half-integer and integer. There is also a contribution of the same structure as that of nuclear quadrupole moment.
- Article. Lee R. N., Milsteǐn A. I., Strakhovenko V. M. Quasiclassical Green function in an external field and small-angle scattering processes // Journal of Experimental and Theoretical Physics. Maik Nauka/Interperiodica Publishing. Russian Federation. - P.66-78. - ISSN 10637761. - EISSN 10906509. A representation is obtained for the quasiclassical Green functions of the Dirac and Klein-Gordon equations allowing for the first nonvanishing correction in an arbitrary localized potential which generally possesses no spherical symmetry. This is used to obtain a solution of these equations in an approximation similar to the Furry-Sommerfeld-Maue approximation. It is shown that the quasiclassical Green function does not reduce to the Green function obtained in the eikonal approximation and has a wider range of validity. This is illustrated by calculating the amplitude of small-angle scattering of a charged particle and the amplitude of Delbrück forward scattering. A correction proportional to the scattering angle was obtained for the amplitude of charged particle scattering in a potential possessing no spherical symmetry. The real part of the Delbrück forward scattering amplitude was calculated in a screened Coulomb potential. © 2000 MAIK "Nauka/Interperiodica".
- Article. Hütt M. Th, L'vov A. I., Milstein A. I., Schumacher M. Compton scattering by nuclei // Physics Reports. Elsevier BV. Netherlands. - P.457-594. - ISSN 03701573. The concept of Compton scattering by even-even nuclei from giant-resonance to nucleon-resonance energies and the status of experimental and theoretical researches in this field are outlined. The description of Compton scattering by nuclei starts from different complementary approaches, namely from second-order S-matrix and from dispersion theories. Making use of these, it is possible to incorporate into the predicted nuclear scattering amplitudes all the information available from other channels, viz. photon-nucleon and photon-meson channels, and to efficiently make use of models of the nucleon, the nucleus and the nucleon-nucleon interaction. The total photoabsorption cross section constrains the nuclear scattering amplitude in the forward direction. The specific information obtained from Compton scattering therefore stems from the angular dependence of the nuclear scattering amplitude, providing detailed insight into the dynamics of the nuclear and nucleon degrees of freedom and into the interplay between them. Nuclear Compton scattering in the giant-resonance energy-region provides information on the dynamical properties of the in-medium mass of the nucleon. Most prominently, the electromagnetic polarizabilities of the nucleon in the nuclear medium can be extracted from nuclear Compton scattering data obtained in the quasi-deuteron energy-region. In our description of this latter process special emphasis is laid upon the exploration of many-body and two-body effects entering into the nuclear dynamics. Recent results are presented for two-body effects due to the mesonic seagull amplitude and due to the excitation of nucleon internal degrees of freedom accompanied by meson exchanges. Due to these studies the in-medium electromagnetic polarizabilities are by now well understood, whereas the understanding of nuclear Compton scattering in the Δ-resonance range is only at the beginning. Furthermore, phenomenological methods how to include retardation effects in the scattering amplitude are discussed and compared with model predictions. © 2000 Elsevier Science B.V.
- Article. Akhmetshin R. R., Anashkin E. V., Arpagaus M., Aulchenko V. M., Banzarov V. Sh, Barkov L. M., Bashtovoy N. S., Bondar A. E., Bondarev D. V., Bragin A. V., Chernyak D. V., Eidelman S. I., Fedotovitch G. V., Gabyshev N. I., Grebeniuk A. A., Grigoriev D. N., Hughes V. W., Karpov S. V., Kazanin V. F., Khazin B. I., Koop I. A., Korostelev M. S., Krokovny P. P., Kurdadze L. M., Kuzmin A. S., Logashenko I. B., Lukin P. A., Mikhailov K. Yu, Milstein A. I., Nesterenko I. N., Okhapkin V. S., Otboev A. V., Polunin A. A., Popov A. S., Purlatz T. A., Root N. I., Ruban A. A., Ryskulov N. M., Shamov A. G., Shatunov Yu M., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Skrinsky A. N., Smakhtin V. P., Snopkov I. G., Solodov E. P., Stepanov P. Yu, Sukhanov A. I., Thompson J. A., Titov V. M., Valishev A. A., Yudin Yu V., Zverev S. G. Cross section of the reaction e+e- → π+π-π+π- below 1 GeV at CMD-2 // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.190-197. - ISSN 03702693. Using 3.07 pb-1 of data collected in the energy range 0.60-0.97 GeV by CMD-2, about 150 events of the process e+e- → π+ π-π+π- have been selected. The energy dependence of the cross section agrees with the assumption of the a1(1260)π intermediate state which is dominant above 1 GeV. For the first time π+π-π+π- events are observed at the ρ meson energy. Under the assumption that all these events come from the ρ meson decay, the value of the cross section at the ρ meson peak corresponds to the following decay width: Γ(ρ0→π+π-π+π-) = (28 ± 1.4 ± 0.5) keV or to the branching ratio B(ρ0→π+π-π+π-) = (1.8 ± 0.9 ± 0.3)·10-5. (C) 2000 Published by Elsevier Science B.V.
- Article. Lee R. N., Milstein A. I. Coulomb corrections to the e+e- pair production in ultrarelativistic heavy-ion collisions // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.321031-321034. - ISSN 10941622. We manifest the origin of the wrong conclusion made by several groups of authors on the absence of Coulomb corrections to the cross section of the e+e- pair production in ultrarelativistic heavy-ion collisions. The source of the mistake is connected with an incorrect passage to the limit in the expression for the cross section. When this error is eliminated, the Coulomb corrections do not vanish, and agree with the results obtained within the Weizsäcker-Williams approximation.
- Article. Akhmetshin R. R., Anashkin E. V., Aulchenko V. M., Banzarov V. Sh, Barkov L. M., Baru S. E., Bondar A. E., Bragin A. V., Chernyak D. V., Eidelman S. I., Bashtovoy N. S., Fedotovich G. V., Gabyshev N. I., Grebeniuk A. A., Grigoriev D. N., Ignatov F. V., Ivanov P. M., Karpov S. V., Kazanin V. F., Khazin B. I., Koop I. A., Krokovny P. P., Kurdadze L. M., Kuzmin A. S., Logashenko I. B., Lukin P. A., Lysenko A. P., Mikhailov K. Yu, Milstein A. I., Nesterenko I. N., Okhapkin V. S., Perevedentsev E. A., Polunin A. A., Popov A. S., Purlatz T. A., Root N. I., Ruban A. A., Ryskulov N. M., Shamov A. G., Shatunov Yu M., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Skrinsky A. N., Smakhtin V. P., Snopkov I. G., Solodov E. P., Stepanov P. Yu, Sukhanov A. I., Yudin Yu V., Zverev S. G., Thompson J. A. Study of the process e+e- → π+π-π+π-π0 with the CMD-2 detector // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.125-130. - ISSN 03702693. The process e+e- → π+π-π+π-π0 has been studied in the center of mass energy range 1280 - 1380 MeV using 3.0 pb-1 of data collected with the CMD-2 detector in Novosibirsk. Analysis shows that the cross section of the five pion production is dominated by the contributions of the ηπ+π- and ωπ+π- intermediate states. (C) 2000 Published by Elsevier Science B.V.
- Article. Akhmetshin R. R., Anashkin E. V., Arpagaus M., Aulchenko V. M., Banzarov V. Sh, Barkov L. M., Bashtovoy N. S., Bondar A. E., Bondarev D. V., Bragin A. V., Chernyak D. V., Eidelman S. I., Fedotovitch G. V., Gabyshev N. I., Grebeniuk A. A., Grigoriev D. N., Hughes V. W., Ignatov F. V., Ivanov P. M., Karpov S. V., Kazanin V. F., Khazin B. I., Koop I. A., Korostelev M. S., Krokovny P. P., Kurdadze L. M., Kuzmin A. S., Logashenko I. B., Lukin P. A., Mikhailov K. Yu, Milstein A. I., Nesterenko I. N., Okhapkin V. S., Otboev A. V., Perevedentsev E. A., Popov A. S., Purlatz T. A., Redin S. I., Root N. I., Ruban A. A., Ryskulov N. M., Shamov A. G., Shatunov Yu M., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Skrinsky A. N., Smakhtin V. P., Snopkov I. G., Solodov E. P., Stepanov P. Yu, Sukhanov A. I., Thompson J. A., Titov V. M., Valishev A. A., Yudin Yu V., Zverev S. G. Observation of the φ → π+π-π+π- decay // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.81-89. - ISSN 03702693. Using 11.6 pb-1 of data collected in the energy range 0.984-1.06 GeV by CMD-2 at VEPP-2M, the cross section of the reaction e+e- → π+π-π+π- has been studied. For the first time an interference pattern was observed in the energy dependence of the cross section near the φ meson. The branching ratio of the φ → π+π-π+π- decay double suppressed by the G-parity and OZI rule is measured Br(φ → π+π-π+π-) = (3.93 ± 1.74 ± 2.14) x 10-6. The upper limits have been placed for the decays φ → π+π-π+π-π0 and ηπ+ Br(φ → π+π-π+π-π0) < 4.6 x 10-6 90% CL, Br(φ → ηπ+π-) < 1.8 x 10-5 90% CL. (C) 2000 Published by Elsevier Science B.V.
- Article. Lee R. N., Milstein A. I., Schumacher M. Relativistic corrections to the electromagnetic polarizabilities of compound systems // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.1-11. - ISSN 10941622. The low-energy Compton scattering amplitude for a system of two particles with masses m1,2 and charges e1,2, bound by electromagnetic forces, was calculated. The complete result for the first relativistic corrections to the electromagnetic polarizabilities, including the tensor part that exists for the total spin S1 was obtained. It was shown that this tensor part contains the quadrupole moment of the system and not any higher multipoles.
- Article. Akhmetshin R. R., Anashkin E. V., Aulchenko V. M., Banzarov V. Sh, Baratt A., Barkov L. M., Baru S. E., Bashtovoy N. S., Bondar A. E., Bondarev D. V., Bragin A. V., Chernyak D. V., Eidelman S. I., Fedotovitch G. V., Gabyshev N. I., Grebeniuk A. A., Grigoriev D. N., Hughes V. W., Ignatov F. V., Karpov S. V., Kazanin V. F., Khazin B. I., Koop I. A., Krokovny P. P., Kurdadze L. M., Kuzmin A. S., Logashenko I. B., Lukin P. A., Lysenko A. P., Mikhailov K. Yu, Milstein A. I., Nesterenko I. N., Okhapkin V. S., Otboev A. V., Perevedentsev E. A., Popov A. S., Root N. I., Ruban A. A., Ryskulov N. M., Shamov A. G., Shatunov Yu M., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Skrinsky A. N., Smakhtin V. P., Snopkov I. G., Solodov E. P., Stepanov P. Yu, Sukhanov A. I., Thompson J. A., Valishev A. A., Yudin Yu V., Zverev S. G. Study of the process e+e- → ηγ in c.m. energy range 600-1380 MeV at CMD-2 // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.217-226. - ISSN 03702693. The cross section of the process e+e- → ηγ has been measured in the 600-1380 MeV c.m. energy range with the CMD-2 detector. The following branching ratios have been determined: B(ρ → ηγ) = (3.28 ± 0.37 ± 0.23) × 10-4, B(ω → ηγ) = (5.10 ± 0.72 ± 0.34) × 10-4, B(φ → ηγ) = (1.287 ± 0.013 ± 0.063) × 10-2. Evidence for the ρ (1450) → ηγ decay has been obtained for the first time. © 2001 Elsevier Science B.V.
- Article. Lee R. N., Milstein A. I., Schumacher M. Relativistic corrections to the electric polarizability of compound systems // Physical Review Letters. American Physical Society. United States. - P.051601/1-051601/4. - ISSN 00319007. - EISSN 10797114. To understand the importance of different relativistic corrections for the electric polarizability, the example of a system where the relativistic corrections can be obtained is considered. A complete set of the relativistic corrections to α 0 following from the Breit Hamiltonian is presented.
- Article. Lee R. N., Milstein A. I., Schumacher M. Relativistic corrections to the electric polarizability of compound systems // Physical Review Letters. American Physical Society. United States. - P.051601/1-051601/4. - ISSN 00319007. - EISSN 10797114. To understand the importance of different relativistic corrections for the electric polarizability, the example of a system where the relativistic corrections can be obtained is considered. A complete set of the relativistic corrections to α0 following from the Breit Hamiltonian is presented.
- Article. Lee R. N., Milstein A. I., Schumacher M. Relativistic corrections to the electromagnetic polarizabilities of compound systems // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.032507/1-032507/11. - ISSN 10941622. The low-energy Compton scattering amplitude for a system of two particles with masses m 1,2 and charges e 1,2, bound by electromagnetic forces, was calculated. The complete result for the first relativistic corrections to the electromagnetic polarizabilities, including the tensor part that exists for the total spin S≥1 was obtained. It was shown that this tensor part contains the quadrupole moment of the system and not any higher multipoles.
- Article. Lee R. N., Milstein A. I. Coulomb corrections and multiple e+e--pair production in ultrarelativistic nuclear collisions // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.032106/1-032106/3. - ISSN 10941622. An attempt was made to demonstrate that the difference in the definitions of the exclusive cross section σ1 and the inclusive cross section σT cannot lead to the cancellation of the Coulomb corrections in the latter. Using the proper regularization of the expression for σT, a result was obtained for the Coulomb corrections that in the limiting case ZAα≪1 agrees with that obtained in the Weizsäcker-Williams approximation.
- Article. Lee R. N., Milstein A. I., Serbo V. G. Structure of the Coulomb and unitarity corrections to the cross section of e<sup>+</sup>e<sup>-</sup> pair production in ultrarelativistic nuclear collisions // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.1-5. - ISSN 10941622. A study was carried out, focusing on the structure of the Coulomb and unitary corrections to the cross section of e+e- pair production and the cross section σn in ultrarelativistic nuclear collisions. The energy dependence of the probability of one pair production at a fixed impact parameter ρ and that of σn was determined.
- Article. Lee R. N., Milstein A. I., Serbo V. G. Structure of the Coulomb and unitarity corrections to the cross section of e+e- pair production in ultrarelativistic nuclear collisions // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.022102/1-022102/5. - ISSN 10941622. A study was carried out, focusing on the structure of the Coulomb and unitary corrections to the cross section of e+e- pair production and the cross section σn in ultrarelativistic nuclear collisions. The energy dependence of the probability of one pair production at a fixed impact parameter ρ and that of σn was determined.
- Article. Akhmetshin R. R., Anashkin E. V., Arbuzov A. B., Aulchenko V. M., Banzarov V. Sh, Barkov L. M., Baru S. E., Bashtovoy N. S., Bondar A. E., Bondarev D. V., Bragin A. V., Chernyak D. V., Dhawan S., Eidelman S. I., Fedotovich G. V., Gabyshev N. I., Gorbachev D. A., Grebenuk A. A., Grigoriev D. N., Hughes V. W., Ignatov F. V., Karpov S. V., Kazanin V. F., Khazin B. I., Koop I. A., Krokovny P. P., Kuraev E. A., Kurdadze L. M., Kuzmin A. S., Logashenko I. B., Lukin P. A., Lysenko A. P., Mikhailov K. Yu, Miller J. P., Milstein A. I., Nesterenko I. N., Okhapkin V. S., Polunin A. A., Popov A. S., Purlatz T. A., Roberts B. L., Root N. I., Ruban A. A., Ryskulov N. M., Shamov A. G., Shatunov Yu M., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Skrinsky A. N., Smakhtin V. P., Snopkov I. G., Solodov E. P., Stepanov P. Yu, Sukhanov A. I., Thompson J. A., Titov V. M., Yudin Yu Y., Zverev S. G. Measurement of e+e- → π+π- cross-section with CMD-2 around ρ-meson // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.161-172. - ISSN 03702693. The cross-section of the process e+e- → π+π- has been measured using about 11 4000 events collected by the CMD-2 detector at the VEPP-2M e+e- collider in the center-of-mass energy range from 0.61 to 0.96 GeV. Results of the pion form factor determination with a 0.6% systematic uncertainty are presented. The following values of the ρ- and ω-meson parameters were found: Mρ = (776.09 ± 0.81) MeV, Γρ = (144.46 ± 1.55) MeV, Γ(ρ → e+e-) = (6.86 ± 0.12) keV, Br(ω → π+π- = (1.33 ± 0.25)%. Implications for the hadronic contribution to the muon anomalous magnetic moment are discussed. © 2002 Elsevier Science B.V. All rights reserved.
- Article. Bondar A. E., Eidelman S. I., Milstein A. I., Pierzchała T., Root N. I., Wa̧s Z., Worek M. Novosibirsk hadronic currents for τ → 4π channels of τ decay library TAUOLA // Computer Physics Communications. Elsevier BV. Netherlands. - P.139-153. - ISSN 00104655. The τ decay into four pions and neutrino was presented. The new parameterization of form factors developed for 4π channels of the τ lepton decay and based on Novosibirsk data on e+e- → 4π and coded in a form suitable for the TAUOLA Monte Carlo package. Its results were compared with the CLEO version of 1998.
- Article. Milstein A. I., Sushkov O. P. Parity nonconservation in heavy atoms: The radiative correction enhanced by the strong electric field of the nucleus // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.022108/1-022108/4. - ISSN 10941622. Parity nonconservation (PNC) in heavy atoms was studied. In particular, radiative corrections enhanced by the strong electric field of the nucleus were calculated. It was shown that in Cs, Tl, Pb, and BI the radiative correction compensates the Breit correction calculated previously.
- Article. Akhmadaliev Sh Zh, Kezerashvili G. Ya, Klimenko S. G., Lee R. N., Malyshev V. M., Maslennikov A. L., Milov A. M., Milstein A. I., Muchnoi N. Yu, Naumenkov A. I., Panin V. S., Peleganchuk S. V., Pospelov G. E., Protopopov I. Ya, Romanov L. V., Shamov A. G., Shatilov D. N., Simonov E. A., Strakhovenko V. M., Tikhonov Yu A. Experimental investigation of high-energy photon splitting in atomic fields // Physical Review Letters. American Physical Society. United States. - P.061802/1-061802/4. - ISSN 00319007. - EISSN 10797114. Photon splitting in atomic fields was experimentally studied. The total statistics collected was 1.6x109 incoming photons with a BGO (bismuth germanate) target and 4x108 without a target for background measurements. Overall, the results confirm the existence of photon splitting phenomenon.
- Article. Lee R. N., Milstein A. I., Schumacher M. Electric polarizabilities of proton and neutron and the relativistic center-of-mass coordinate // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.87-92. - ISSN 03702693. We argue that the relativistic correction δRc.m. to the center-of-mass vector can lead to the approximate equality of the proton and neutron electric polarizabilities in the quark model. The explicit form of δRc.m. depends only on the non-relativistic potential between quarks. In particular, this correction is the same for the potential generated by Lorentz-vector and -scalar interactions. © 2002 Elsevier Science B.V. All rights reserved.
- Article. Karshenboim Savely G., Milstein Alexander I. Delbrück scattering and the g-factor of a bound electron // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.321-324. - ISSN 03702693. The leading contribution of the light-by-light scattering effects to g-factor of a bound electron is derived. The corresponding amplitude is expressed in terms of low-energy Delbrück scattering of a virtual photon. The result reads Δg = (7/216)α(Zα)5. © 2002 Elsevier Science B.V. All rights reserved.
- Article. Milstein A. I., Sushkov O. P., Terekhov I. S. Radiative corrections and parity nonconservation in heavy atoms // Physical Review Letters. American Physical Society. United States. - P.283003/1-283003/4. - ISSN 00319007. - EISSN 10797114. The Zα2 and Z2α3ln(λC/r0) radiative corrections to the effect of atomic parity violation were calculated analytically. This calculation allowed to perform a consistent analysis of the experimental data. Agreement with the standard model was within 0.5σ.
- Article. Lee R. N., Maslennikov A. L., Milstein A. I., Strakhovenko V. M., Tikhonov Yu A. Photon splitting in atomic fields // Physics Reports. Elsevier BV. Netherlands. - P.213-246. - ISSN 03701573. Photon splitting due to vacuum polarization in the electric field of an atom is considered. We survey different theoretical approaches to the description of this nonlinear QED process and several attempts of its experimental observation. We present the results of the lowest-order perturbation theory as well as those obtained within the quasiclassical approximation being exact in the external field strength. The experiment where photon splitting was really observed for the first time is discussed in details. The results of this experiment are compared with recent theoretical estimations. © 2002 Elsevier Science B.V. All rights reserved.
- Article. Milstein A. I., Sushkov O. P., Terekhov I. S. Calculation of radiative corrections to the effect of parity nonconservation in heavy atoms // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.621031-6210312. - ISSN 10941622. A study on calculation of self-energy and the vertex radiative corrections to the effect of parity nonconservation in heavy atoms is presented. It is indicated that the corrections are enhanced by the collective electric field of the nucleus. The dependence of the Lamb shift on the finite nuclear size is also investigated.
- Article. Milstein A. I., Sushkov O. P., Terekhov I. S. Finite nuclear size and Lamb shift of p-wave atomic states // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.621111-621115. - ISSN 10941622. Finite nuclear size (FNS) and Lamb shift of p-wave atomic states were studied. The perturbarion theory expansion for the relative correction for a p1/2 state starts with a αln(1/Zα) term, while for the s1/2 states it starts with a Zα2 term, where α is the fine-structure constant and Z is the nuclear charge. The results show that the structure of the corrections is qualitatively different to that for the s-wave states.
- Article. Akhmetshin R. R., Aulchenko V. M., Banzarov V. Sh, Baratt A., Barkov L. M., Baru S. E., Bashtovoy N. S., Bondar A. E., Bondarev D. V., Bragin A. V., Eidelman S. I., Epifanov D. A., Fedotovitch G. V., Gabyshev N. I., Gorbachev D. A., Grebeniuk A. A., Grigoriev D. N., Hughes V. W., Ignatov F. V., Karpov S. V., Kazanin V. F., Khazin B. I., Koop I. A., Krokovny P. P., Kuzmin A. S., Logashenko I. B., Lukin P. A., Lysenko A. P., Mikhailov K. Yu, Milstein A. I., Nesterenko I. N., Okhapkin V. S., Otboev A. V., Pak A. V., Perevedentsev E. A., Polunin A. A., Popov A. S., Redin S. I., Roberts B. L., Root N. I., Ruban A. A., Ryskulov N. M., Shamov A. G., Shatunov Yu M., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Skrinsky A. N., Snopkov I. G., Solodov E. P., Stepanov P. Yu, Thompson J. A., Valishev A. A., Yudin Yu V., Zaitsev A. S., Zverev S. G. Study of the process e+e- →ωπ0→π0π0γ in c.m. energy range 920-1380 MeV at CMD-2 // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.173-181. - ISSN 03702693. The cross section of the process e+e-→ωπ0→ π0π0γ has been measured in the c.m. energy range 920-1380 MeV with the CMD-2 detector. Its energy dependence is well described by the interference of the ρ(770) and ρ(1450) mesons decaying to ωπ0. Upper limits for the cross sections of the direct processes e+e-→π0π0γ, ηπ0γ have been set. © 2003 Elsevier Science B.V. All rights reserved.
- Article. Khriplovich I. V., Milstein A. I. Corrections to the deuterium hyperfine structure due to deuteron excitations // Zhurnal Eksperimental'noi i Teroreticheskoi Fiziki. Izdatel'stvo Nauka. Russian Federation. - P.205-210. - ISSN 00444510.
- Review. Akhmetshin R. R., Anashkin E. V., Arbuzov A. B., Banzarov V. Sh, Baratt A., Barkov L. M., Bogdan A. V., Bondar A. E., Bondarev D. V., Eidelman S. I., Epifanov D. A., Fedotovich G. V., Gabyshev N. I., Gorbachev D. A., Grebenuk A. A., Grigoriev D. N., Hughes V. W., Ignatov F. V., Kazanin V. F., Khazin B. I., Krokovny P. P., Kuraev E. A., Kurdadze L. M., Kuzmin A. S., Lischenko Yu E., Logashenko I. B., Lukin P. A., Mikhailov K. Yu, Miller J. P., Milstein A. I., Nikulin M. A., Popov A. S., Roberts B. L., Root N. I., Ryskulov N. M., Shatunov Yu M., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Skrinsky A. N., Smakhtin V. P., Solodov E. P., Stepanov P. Yu, Thompson J. A., Zaitsev A. S. Update: A reanalysis of hadronic cross section measurements at CMD-2 // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.285-289. - ISSN 03702693. The updated results of the precise measurements of the processes e +e- → ρ → π+π-, e+e- → ω → π+π -π0 and e+e- → φ → KL 0KS 0 performed by the CMD-2 Collaboration are presented. The update appeared necessary due to an overestimate of the integrated luminosity in previous analyses. © 2003 Elsevier B.V. All rights reserved.
- Article. Milstein A. I., Sushkov O. P., Terekhov I. S. Finite-nuclear-size effect on the Lamb shift of s1/2, p 1/2, and p3/2 atomic states // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.221141-2211410. - ISSN 10941622. The shift of atomic energy level due to finite nuclear size was investigated by considering one-loop self-energy and vacuum polarization radiative corrections. It was observed that in the vicinity of the nucleus, corresponding radiative corrections are strongly affected by the ultrarelativistic behavior of electrons. The next-to-leading nonlogarithmic Zα terms were derived for the self-energy of p1/2 and p 3/2 states in addition to already known terms. The explicit analytic expressions for s1/2 and p1/2 corrections agree with the results of the numerical calculations up to Z=100.
- Article. Lee R. N., Milstein A. I., Strakhovenko V. M. High-energy expansion of Coulomb corrections to the e+e photoproduction cross section // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.227081-2270811. - ISSN 10941622. The correction of order 1/ω to the high-energy total e +e- photoproduction cross section in the electric field of a heavy ion was derived, where ω was the photon energy. The consideration was based on the use of quasiclassical electron Green's function and the next-to-leading correction to the cross section was discussed. In the leading approximation, the influence of screening on the Coulomb corrections was examined. It was found that the corrections to the bremsstrahlung spectrum were obtained from the corresponding results for pair production.
- Article. Khriplovich I. B., Milstein A. I. Corrections to deuterium hyperfine structure due to deuteron excitations // Journal of Experimental and Theoretical Physics. Maik Nauka/Interperiodica Publishing. Russian Federation. - P.181-185. - ISSN 10637761. - EISSN 10906509. We consider the corrections to the deuterium hyperfine structure originating from the two-photon exchange between an electron and deuteron, with deuteron excitations in the intermediate states. In particular, the motion of the two intermediate nucleons as a whole is taken into account. The problem is solved in the zero-range approximation. The result is in good agreement with the experimental value of deuterium hyperfme splitting. © 2004 MAIK "Nauka/Interperiodica".
- Article. Akhmetshin R. R., Aulchenko V. M., Banzarov V. Sh, Baratt A., Barkov L. M., Baru S. E., Bashtovoy N. S., Bondar A. E., Bondarev D. V., Bragin A. V., Eidelman S. I., Epifanov D. A., Fedotovitch G. V., Gabyshev N. I., Gorbachev D. A., Grebeniuk A. A., Grigoriev D. N., Ignatov F. V., Karpov S. V., Kazanin V. F., Khazin B. I., Koop I. A., Krokovny P. P., Kuzmin A. S., Logashenko I. B., Lukin P. A., Lysenko A. P., Mikhailov K. Yu, Milstein A. I., Nesterenko I. N., Okhapkin V. S., Otboev A. V., Perevedentsev E. A., Polunin A. A., Popov A. S., Redin S. I., Root N. I., Ruban A. A., Ryskulov N. M., Shamov A. G., Shatunov Yu M., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Skrinsky A. N., Snopkov I. G., Solodov E. P., Stepanov P. Yu, Thompson J. A., Valishev A. A., Yudin Yu V., Zaitsev A. S., Zverev S. G. Study of the process e+e- → π 0π0γ in c.m. energy range 600-970 MeV at CMD-2 // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.119-128. - ISSN 03702693. The cross section of the process e+e- → π0π0γ has been measured in the c.m. energy range 600-970 MeV with the CMD-2 detector. The following branching ratios have been determined: B(ρ0 → π0π 0γ)=(5.2+1.5 -1.3±0.6) ×10-5 and B(ω → π0π 0γ)=(6.4+2.4 -2.0±0.8) ×10-5. Evidence for the ρ0 → f 0(600)γ decay has been obtained: B(ρ0 → f0(600)γ)=(6.0+3.3 -2.7±0.9) ×10-5. From a search for the process e+e - → ηπ0γ the following upper limit has been obtained: B(ω → ηπ0γ)<3. 3×10-5 at 90% CL. © 2003 Published by Elsevier B.V.
- Article. Milstein A. I., Terekhov I. S. Scattering of a low-energy electron in a strong Coulomb field // Journal of Experimental and Theoretical Physics. Maik Nauka/Interperiodica Publishing. Russian Federation. - P.687-690. - ISSN 10637761. - EISSN 10906509. The low-energy electron scattering cross section in a strong Coulomb field is analyzed theoretically. It is shown that the exact cross section in a wide energy range significantly differs from the results obtained in the first Born approximation and in the nonrelativistic approximation. © 2004 MAIK "Nauka/Interperiodica".
- Article. Achasov M. N., Akhmetshin R. R., Aulchenko V. M., Banzarov V. Sh, Baratt A., Barkov L. M., Baru S. E., Bashtovoy N. S., Beloborodov K. I., Berdugin A. V., Bogdanchikov A. G., Bondar A. E., Bondarev D. V., Bozhenok A. V., Bragin A. V., Bukin A. D., Bukin D. A., Dimova T. V., Druzhinin V. P., Eidelman S. I., Epifanov D. A., Fedotovitch G. V., Gabyshev N. I., Gorbachev D. A., Grebeniuk A. A., Grigoriev D. N., Hughes V. W., Ignatov F. V., Karpov S. V., Kazanin V. F., Khazin B. I., Koop I. A., Korol A. A., Koshuba S. V., Krokovny P. P., Kuzmin A. S., Logashenko I. B., Lukin P. A., Lysenko A. P., Mikhailov K. Y., Milstein A. I., Nesterenko I. N., Okhapkin V. S., Otboev A. V., Pakhtusova E. V., Perevedentsev E. A., Polunin A. A., Popov A. S., Redin S. I., Root N. I., Ruban A. A., Ryskulov N. M., Serednyakov S. I., Shamov A. G., Shatunov Y. M., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Silagadze Z. K., Skrinsky A. N., Snopkov I. G., Solodov E. P., Thompson J. A., Usov Y. V., Valishev A. A., Vasiljev A. V., Yudin Y. V., Zaitsev A. S., Zverev S. G. Recent results of the study of hadronic production with the CMD-2 and SND detectors at the VEPP-2M collider // European Physical Journal C. Springer Verlag. Germany. - P.s583-s585. - ISSN 14346044. - EISSN 14346052.
- Article. Akhmetshin R. R., Aulchenko V. M., Banzarov V. Sh, Baratt A., Barkov L. M., Bashtovoy N. S., Bondar A. E., Bondarev D. V., Bragin A. V., Eidelman S. I., Epifanov D. A., Fedotovitch G. V., Gabyshev N. I., Gorbachev D. A., Grebeniuk A. A., Grigoriev D. N., Ignatov F. V., Karpov S. V., Kazanin V. F., Khazin B. I., Koop I. A., Krokovny P. P., Kuzmin A. S., Logashenko I. B., Lukin P. A., Lysenko A. P., Mikhailov K. Yu, Milstein A. I., Nesterenko I. N., Okhapkin V. S., Otboev A. V., Perevedentsev E. A., Polunin A. A., Popov A. S., Redin S. I., Root N. I., Ruban A. A., Ryskulov N. M., Shamov A. G., Shatunov Yu M., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Skrinsky A. N., Snopkov I. G., Solodov E. P., Thompson J. A., Valishev A. A., Yudin Yu V., Zaitsev A. S., Zverev S. G. Total cross section of the process e+e- → π+π-π+π- in the c.m. energy range 980-1380 MeV // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.101-108. - ISSN 03702693. The e+e-→π+π -π+π- cross section has been measured using 5.8 pb-1 of integrated luminosity collected with the CMD-2 detector at the VEPP-2M collider. Analysis of the data with a refined efficiency determination and use of both three- and four-track events allowed doubling of a data sample and reduction of systematic errors to 5-7%. © 2004 Elsevier B.V. All rights reserved.
- Erratum. Lee R. N., Milstein A. I., Strakhovenko V. M. Erratum: High-energy expansion of Coulomb corrections to the e +e- photoproduction cross section (Physical Review A (2004) 69 (022708)) // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.059902-1. - ISSN 10941622.
- Article. Akhmetshin R. R., Aulchenko V. M., Banzarov V. Sh, Baratt A., Barkov L. M., Bashtovoy N. S., Bondar A. E., Bondarev D. V., Bragin A. V., Eidelman S. I., Epifanov D. A., Fedotovitch G. V., Gabyshev N. I., Gorbachev D. A., Grebeniuk A. A., Grigoriev D. N., Ignatov F. V., Karpov S. V., Kazanin V. F., Khazin B. I., Koop I. A., Krokovny P. P., Kuzmin A. S., Lischenko Yu E., Logashenko I. B., Lukin P. A., Mikhailov K. Yu, Milstein A. I., Nesterenko I. N., Okhapkin V. S., Otboev A. V., Popov A. S., Redin S. I., Roberts B. L., Root N. I., Ruban A. A., Ryskulov N. M., Shamov A. G., Shatunov Yu M., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Skrinsky A. N., Snopkov I. G., Solodov E. P., Thompson J. A., Valishev A. A., Yudin Yu V., Zaitsev A. S., Zverev S. G. Study of the processes e +e -→ ηγ, π 0γ → 3γ in the c.m. energy range 600-1380 MeV at CMD-2 // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.26-36. - ISSN 03702693. The processes e+e-→ηγ, π0γ→3γ have been studied in the c.m. energy range 600-1380 MeV with the CMD-2 detector. The following branching ratios have been determined: B(ρ0→ηγ)=(3. 21±1.39±0.20)×10-4,B(ω→ηγ)=(4.44-1. 83+2.59±0.28)×10-4,B(φ→ηγ)=(1.373±0. 014±0.085)×10-2,B(ρ0→π0γ)=(6.21-1.18+1. 28±0.39)×10-4,B(ω→π0γ)=(9.06±0. 20±0.57)×10-2,B(φ→π0γ)=(1.258±0. 037±0.077)×10-3. © 2004 Elsevier B.V. All rights reserved.
- Article. Lee R. N., Milstein A. I., Strakhovenko V. M., Schwarz O. Ya Coulomb corrections to bremsstrahlung in the electric field of a heavy atom at high energies // Journal of Experimental and Theoretical Physics. Maik Nauka/Interperiodica Publishing. Russian Federation. - P.1-13. - ISSN 10637761. - EISSN 10906509. We consider the differential and partially integrated cross sections for bremsstrahlung from high-energy electrons in an atomic field, with this field taken into account exactly. We use the semiclassical electron Green function and wavefunctions in an external electric field. It is shown that the Coulomb corrections to the differential cross section are very susceptible to screening. Nevertheless, the Coulomb corrections to the cross section summed over the final-electron states are independent of screening in the leading approximation in the small parameter 1/mrscr (rscr is the screening radius and m is the electron mass, ℏ = c = 1). We also consider bremsstrahlung from a finite-size electron beam on a heavy nucleus. The Coulomb corrections to the differential probability are also very susceptible to the beam shape, while the corrections to the probability integrated over momentum transfer are independent of it, apart from the trivial factor, which is the electron-beam density at zero impact parameter. For the Coulomb corrections to the bremsstrahlung spectrum, the next-to-leading terms with respect to the parameters m/ε (ε is the electron energy) and 1/mrscr are obtained. © 2005 Pleiades Publishing, Inc.
- Article. Milstein A. I., Sushkov O. P. Vacuum polarization radiative correction to parity violating electron scattering on heavy nuclei // Physical Review C - Nuclear Physics. American Physical Society. United States. - ISSN 05562813. - EISSN 1089490X. The effect of vacuum polarization on the parity violating asymmetry in elastic electron-nucleus scattering is considered. Calculations are performed in the high-energy approximation, with an exact treatment of the electric field of the nucleus. It is shown that the radiative correction to the parity violating asymmetry is logarithmically enhanced and the value of the correction is about -1%. ©2005 The American Physical Society.
- Article. Akhmetshin R. R., Aulchenko V. M., Banzarov V. Sh, Baratt A., Barkov L. M., Bashtovoy N. S., Bondar A. E., Bondarev D. V., Bragin A. V., Eidelman S. I., Epifanov D. A., Fedotovitch G. V., Gabyshev N. I., Gorbachev D. A., Grebeniuk A. A., Grigoriev D. N., Ignatov F. V., Karpov S. V., Kazanin V. F., Khazin B. I., Koop I. A., Krokovny P. P., Kuzmin A. S., Logashenko I. B., Lukin P. A., Lysenko A. P., Mikhailov K. Yu, Milstein A. I., Nesterenko I. N., Nikulin M. A., Okhapkin V. S., Otboev A. V., Perevedentsev E. A., Polunin A. A., Popov A. S., Redin S. I., Root N. I., Ruban A. A., Ryskulov N. M., Shamov A. G., Shatunov Yu M., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Skrinsky A. N., Snopkov I. G., Solodov E. P., Thompson J. A., Valishev A. A., Yudin Yu V., Zaitsev A. S., Zverev S. G. Study of the ρ and ω meson decays into a pseudoscalar meson and e+e- pair with the CMD-2 detector // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.29-38. - ISSN 03702693. Using 3.3 pb-1 of data collected with the CMD-2 detector in the 720-840 MeV c.m. energy range, the branching fraction of the conversion decay ω→π0e+e- has been measured: B(ω→π0e+e-)=(8.19±0. 71±0.62)×10-4. The upper limits for the branching fractions of the following conversion decays have been obtained at the 90% confidence level: B(ρ→π0e+e -)<1.6×10-5, B(ρ→ηe +e-)<0.7×10-5 and B(ω→η e+e-)<1.1×10-5. © 2005 Elsevier B.V. All rights reserved.
- Article. Lee R. N., Milstein A. I., Terekhov I. S., Karshenboim S. G. Virtual light-by-light scattering and the g factor of a bound electron // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. The contribution of the light-by-light diagram to the g factor of an electron and muon bound in a Coulomb field is obtained. For an electron in a ground state, our results are in good agreement with the results of other authors obtained numerically for large Z. For relatively small Z our results have essentially higher accuracy as compared to the previous ones. For muonic atoms, the contribution is obtained with a high accuracy in the whole region of Z. © 2005 The American Physical Society.
- Article. Karshenboim S. G., Lee R. N., Milstein A. I. G factor of an electron or muon bound by an arbitrary central potential // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. We consider the g factor of a spin-12 particle (electron or muon) bound by an arbitrary central field. We present an approach that allows one to express the relativistic g factor in terms of the binding energy. We derive the general expression for the correction to the g factor caused by a deviation of the central potential from the Coulomb one. As the application of this method, we consider the corrections to the g factor due to the finite nuclear size, including vacuum polarization radiative correction. The effect of the anomalous magnetic moment is also taken into account. © 2005 The American Physical Society.
- Article. Milstein A. I., Terekhov I. S., Jentschura U. D., Keitel C. H. Laser-dressed vacuum polarization in a Coulomb field // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. We investigate quantum electrodynamic effects under the influence of an external, time-dependent electromagnetic field, which mediates dynamic modifications of the radiative corrections. Specifically, we consider the quantum electrodynamic vacuum-polarization tensor under the influence of two external background fields: a strong laser field and a nuclear Coulomb field. We calculate the charge and current densities induced by a nuclear Coulomb field in the presence of a laser field. We find the corresponding induced scalar and vector potentials. The induced potential, in first-order perturbation theory, leads to a correction to atomic energy levels. The external laser field breaks the rotational symmetry of the system. Consequently, the induced charge density is not spherically symmetric, and the energy correction therefore leads to a "polarized Lamb shift." In particular, the laser generates an additional potential with a quadrupole moment. The corresponding laser-dressed vacuum-polarization potential behaves like 1/r3 at large distances, unlike the Uehling potential, which vanishes exponentially for large r. The energy corrections are of the same order of magnitude for hydrogenic levels, irrespective of the angular momentum quantum number. The induced current leads to a transition dipole moment which oscillates at the second harmonic of the laser frequency and is mediated by second-order harmonic generation in the vacuum-polarization loop. In the far field, at distances r1/ω from the nucleus (ω is the laser frequency), the laser induces mutually perpendicular electric and magnetic fields, which give rise to an energy flux that corresponds to photon fusion leading to the generation of real photons, again at the second harmonic of the laser. Our investigation might be useful for other situations where quantum field theoretic phenomena are subjected to external fields of a rather involved structure. © 2005 The American Physical Society.
- Article. Milstein A. I., Strakhovenko V. M. Polarizing mechanisms for stored p and p̄ beams interacting with a polarized target // Physical Review E - Statistical, Nonlinear, and Soft Matter Physics. American Physical Society. United States. - ISSN 15393755. The kinetics of the polarization buildup during the interaction of stored protons (antiprotons) with a polarized target is considered. It is demonstrated that for small scattering angles, when a projectile remains in the beam, the polarization buildup is completely due to the spin-flip transitions. The corresponding cross sections turn out to be negligibly small for a hydrogen gas target as well as for a pure electron target. For the latter, the filtering mechanism also does not provide a noticeable beam polarization. © 2005 The American Physical Society.
- Article. Lee R. N., Milstein A. I., Karshenboim S. G. Corrections to the energy levels of a spin-zero particle bound in a strong field // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. Formulas for the corrections to the energy levels and wave functions of a spin-zero particle bound in a strong field are derived. The general case of the sum of a Lorentz-scalar potential and zero component of a Lorentz-vector potential is considered. The forms of the corrections differ essentially from those for spin- 1 2 particles. As an example of application of our results, we evaluated the electric polarizability of a ground state of a spin-zero particle bound in a strong Coulomb field. © 2006 The American Physical Society.
- Article. Lüscher Andreas, Misguich Grégoire, Milstein Alexander I., Sushkov Oleg P. Local spin spirals in the Néel phase of La2-x Srx Cu O4 // Physical Review B - Condensed Matter and Materials Physics. American Physical Society. United States. - ISSN 10980121. Experimental observations of lightly doped La2-x Srx Cu O4, x<0.02, revealed remarkable magnetic properties such as the incommensurate noncollinear ordering (additional to the Néel ordering) and a tremendous doping dependence of the uniform longitudinal susceptibility. We show that the spiral solution of the t- t′ - t″ -J model obtained by taking into account the Coulomb trapping of holes by Sr ions describes these puzzling data perfectly well. Our solution firstly explains why the incommensurate structure is directed along the orthorhombic b axis, and secondly allows a numerical calculation of the positions and shapes of the incommensurate neutron scattering peaks. Thirdly, we calculate the doping dependence of the spin-wave gap, and lastly, we study the longitudinal magnetic susceptibility and show that its doping dependence is due to the noncollinearity of the spin spiral. © 2006 The American Physical Society.
- Article. Milstein A. I., Müller C., Hatsagortsyan K. Z., Jentschura U. D., Keitel C. H. Polarization-operator approach to electron-positron pair production in combined laser and Coulomb fields // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. The optical theorem is applied to the process of electron-positron pair creation in the superposition of a nuclear Coulomb and a strong laser field. We derive representations for the total production rate as twofold integrals, both for circular laser polarization and for the general case of elliptic polarization. Our approach allows us to obtain, by analytical means, the asymptotic behavior of the pair creation rate for various limits of interest. In particular, we consider pair production by two-photon absorption and show that, close to the energetic threshold of this process, the rate obeys a power law in the laser frequency with different exponents for linear and circular laser polarization. With the help of the upcoming x-ray laser sources, our results could be tested experimentally. © 2006 The American Physical Society.
- Article. Lee R. N., Milstein A. I., Strakhovenko V. M., Schwartz O. Ya Electron-positron pair production and bremsstrahlung at intermediate energies in the field of heavy atoms // Radiation Physics and Chemistry. Pergamon Press Ltd.. United Kingdom. - P.868-873. - ISSN 0969806X. The Coulomb corrections (CC) to the processes of bremsstrahlung and pair production are investigated. The next-to-leading term in the high-energy asymptotics is found. This term becomes very essential in the region of intermediate energies. The influence of screening for CC is small for differential cross section, spectrum, and the total cross section of pair production. The same is true for the spectrum of bremsstrahlung, but not for the differential cross section, where the influence of screening can be very large. The corresponding screening corrections as well as the modification of the differential cross section of bremsstrahlung are found. A comparison of our results for the total cross section of pair production with the experimental data available is performed. This comparison has justified our analytical results and allowed to elaborate a simple ansatz for the next-to-leading correction. The influence of the electron beam shape on CC for bremsstrahlung is investigated. It turns out that the differential cross section is very sensitive to this shape. © 2006 Elsevier Ltd. All rights reserved.
- Article. Akhmetshin R. R., Aulchenko V. M., Banzarov V. Sh, Barkov L. M., Bashtovoy N. S., Bondar A. E., Bondarev D. V., Bragin A. V., Eidelman S. I., Epifanov D. A., Fedotovich G. V., Gabyshev N. I., Gorbachev D. A., Grebeniuk A. A., Grigoriev D. N., Ignatov F. V., Karpov S. V., Kazanin V. F., Khazin B. I., Koop I. A., Krokovny P. P., Kuzmin A. S., Logashenko I. B., Lukin P. A., Lysenko A. P., Mikhailov K. Yu, Milstein A. I., Nesterenko I. N., Nikulin M. A., Okhapkin V. S., Otboev A. V., Perevedentsev E. A., Popov A. S., Redin S. I., Root N. I., Ruban A. A., Ryskulov N. M., Shatunov Yu M., Shwartz B. A., Sibidanov A. L., Sidorov V. A., Skrinsky A. N., Smakhtin V. P., Snopkov I. G., Solodov E. P., Yudin Yu V., Zaitsev A. S., Zverev S. G. Study of φ{symbol} → π+ π- π0 with CMD-2 detector // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.203-209. - ISSN 03702693. The cross section of the process e+ e- → π+ π- π0 has been measured in the c.m. energy range 984-1060 MeV with the CMD-2 detector at the VEPP-2M collider. The obtained value of Br (φ{symbol} → e+ e-) Br (φ{symbol} → π+ π- π0) = (4.51 ± 0.16 ± 0.11) × 10-5 is in good agreement with the previous measurements and has the best accuracy. Analysis of the Dalitz plot was performed. The contributions of the dominant φ{symbol} → ρ π mechanism as well as of a small direct φ{symbol} → 3 π amplitude were determined. © 2006 Elsevier B.V. All rights reserved.
- Article. Dmitriev V. F., Milstein A. I. Final State Interaction Effects in N over(N, -) Production near Threshold // Nuclear Physics B - Proceedings Supplements. North-Holland Publ Co. Netherlands. - P.53-56. - ISSN 09205632. We use the Paris nucleon-antinucleon optical potential for explanation of experimental data in the process e + e - → p over(p, -) near threshold. It is shown that the cross section and electromagnetic form factors are very sensitive to the parameters of the potential. It turns out that final-state interaction due to a slightly modified absorptive part of the potential allows us to reproduce experimental data available. © 2006 Elsevier B.V. All rights reserved.
- ConferencePaper. Levchuk M. I., L'vov A. I., Milstein A. I., Schumacher M. Structure of the σ -meson and diamagnetism of the nucleon // The structure of the a meson and the diamagnetism of the nucleon are shown to be topics which are closely related to each other. Arguments are found that the γ meson couples to two photons via its non-strange qq structure component. This ansatz leads to a quantitative explanation of the t-channel component of the difference of electromagnetic polarizabilities, (α - β)t, containing the diamagnetism of the nucleon. The prediction is (α - β)t pn = (5αegπNN)/ (6π2m2fπ) = 15.3 in units of 10-4fm 3 to be compared with the experimental values (α-β) t p = 15.1±1.3 for the proton and (α-β)=14.8±2.7 for the neutron. The equivalent approach to exploit the ππstructure component of the Σ meson via the BEFT sum rule leads to (a - β)t p,n = 14 ± 2, what also is in agreement with the experimental results. Copyright © 2006 by World Scientific Publishing Co. Pvt. Ltd.
- Article. Lüscher Andreas, Milstein Alexander I., Sushkov Oleg P. Structure of the spin-glass state of La2-xSrxCuO4: The spiral theory // Physical Review Letters. American Physical Society. United States. - ISSN 00319007. - EISSN 10797114. Starting from the t-J model, we derive the effective field theory describing the spin dynamics in insulating La2-xSrxCuO4, x 0.055, at low temperature. The theory results in a disordered spiral ground state, in which the staggered component of the copper spins is confined in a plane determined by the spin anisotropies. The static spin structure factor obtained in our calculations is in perfect agreement with neutron scattering data over the whole range of doping in both, the Néel and the spin-glass phase. We show that topological defects (spin vortex-antivortex pairs) are an intrinsic property of the disordered spiral ground state. © 2007 The American Physical Society.
- Article. Lee R. N., Milstein A. I. E + e - Pair production in ultrarelativistic heavy-ion collisions at intermediate impact parameters // Journal of Experimental and Theoretical Physics. Maik Nauka/Interperiodica Publishing. Russian Federation. - P.423-430. - ISSN 10637761. - EISSN 10906509. Using the semiclassical Green's function in the Coulomb field, we analyze the probabilities of single and multiple e + e - pair production at a fixed impact parameter b between colliding ultrarelativistic heavy nuclei. We perform calculations in the Born approximation with respect to the parameter Z Bα and exactly in Z Aα, where Z A and Z B are the charge numbers of the corresponding nuclei. We also obtain the approximate formulas for the probabilities valid for Z Aα, Z Bα ≲ 1. © Nauka/Interperiodica 2007.
- ConferencePaper. Lee R. N., Milstein A. I., Terekhov I. S., Karshenboim S. G. g Factor of the bound electron and muon // Canadian Journal of Physics. NRC Research Press. Canada. - P.541-549. - ISSN 00084204. - EISSN 12086045. Quantum electrodynamics (QED) corrections to the g factor of the bound electron and muon in the hydrogenlike atom are discussed. An approach that allows one to express the relativistic g factor of spin-1/2 particle in terms of the binding energy is applied to the calculation of the corrections to the g factor due to the finite nuclear size, including the vacuum polarization radiative correction. The contribution of the light-by-light diagram to the g factor of the bound electron and muon is calculated. For light one-electron ions, which are important for the experiment, this contribution has, so far, not been known. © 2007 NRC Canada.
- Article. Lüscher Andreas, Milstein Alexander I., Sushkov Oleg P. Effective action of the weakly doped t-J model and spin-wave excitations in the spin-glass phase of La2-x Srx Cu O4 // Physical Review B - Condensed Matter and Materials Physics. American Physical Society. United States. - ISSN 10980121. We derive the low-energy effective field theory of the extended t-J model in the regime of light doping. The action includes a previously unknown Berry phase term, which is discussed in detail. We use this effective field theory to calculate spin-wave excitations in the disordered spin spiral state of La2-x Srx Cu O4 (the spin-glass phase). We predict an excitation spectrum with two distinct branches: The in-plane mode has the usual linear spin-wave dispersion and the out-of-plane mode shows nontrivial doping dependent features. We also calculate the intensities for inelastic neutron scattering in these modes. © 2007 The American Physical Society.
- Article. Boie H., Scheit H., Jentschura U. D., Köck F., Lauer M., Milstein A. I., Terekhov I. S., Schwalm D. Bremsstrahlung in α decay reexamined // Physical Review Letters. American Physical Society. United States. - ISSN 00319007. - EISSN 10797114. A high-statistics measurement of bremsstrahlung emitted in the α decay of Po210 has been performed, which allows us to follow the photon spectra up to energies of ∼500keV. The measured differential emission probability is in good agreement with our theoretical results obtained within the quasiclassical approximation as well as with the exact quantum mechanical calculation. It is shown that, due to the small effective electric dipole charge of the radiating system, a significant interference between the electric dipole and quadrupole contributions occurs, which is altering substantially the angular correlation between the α particle and the emitted photon. © 2007 The American Physical Society.
- Article. Di Piazza A., Milstein A. I., Keitel C. H. Photon splitting in a laser field // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. Photon splitting due to vacuum polarization in a laser field is considered. Using an operator technique, we derive the amplitudes for arbitrary strength, spectral content, and polarization of the laser field. The case of a monochromatic circularly polarized laser field is studied in detail, and the amplitudes are obtained as threefold integrals. The asymptotic behavior of the amplitudes for various limits of interest is investigated also in the case of a linearly polarized laser field. Using the results obtained, the possibility of experimental observation of the process is discussed. © 2007 The American Physical Society.
- Article. Dmitriev V. F., Milstein A. I. Final state interaction effects in the e+ e- → N over(N, ̄) process near threshold // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.13-16. - ISSN 03702693. We use the Paris nucleon-antinucleon optical potential for explanation of experimental data in the process e+ e- → p over(p, ̄) near threshold. It is shown that the cross section and the electromagnetic form factors are very sensitive to the parameters of the potential. It turns out that final-state interaction due to slightly modified absorptive part of the potential allows us to reproduce available experimental data. We also demonstrated that the cross section in n over(n, ̄) channel is larger than that in p over(p, ̄) one, and their ratio is almost energy independent up to 2.2 GeV. © 2007 Elsevier B.V. All rights reserved.
- Article. Jentschura U. D., Milstein A. I., Terekhov I. S., Boie H., Scheit H., Schwalm D. Quasiclassical description of bremsstrahlung accompanying α decay including quadrupole radiation // Physical Review C - Nuclear Physics. American Physical Society. United States. - ISSN 05562813. - EISSN 1089490X. We present a quasiclassical theory of α decay accompanied by bremsstrahlung with a special emphasis on the case of Po210, with the aim of finding a unified description that incorporates both the radiation during the tunneling through the Coulomb wall and the finite energy Eγ of the radiated photon up to Eγ~Qα/η, where Qα is the α-decay Q-value and η is the Sommerfeld parameter. The corrections with respect to previous quasiclassical investigations are found to be substantial, and excellent agreement with a full quantum mechanical treatment is achieved. Furthermore, we find that a dipole-quadrupole interference significantly changes the α-γ angular correlation. We obtain good agreement between our theoretical predictions and experimental results. © 2008 The American Physical Society.
- Article. Sloggett C., Milstein A. I., Sushkov O. P. Correlated electron current and temperature dependence of the conductance of a quantum point contact // European Physical Journal B. Springer Verlag. Germany. - P.427-432. - ISSN 14346028. - EISSN 14346036. We investigate finite temperature corrections to the Landauer formula due to electron-electron interaction within the quantum point contact. When the Fermi level is close to the barrier height, the conducting wavefunctions become peaked on the barrier, enhancing the electron-electron interaction. At the same time, away from the contact the interaction is strongly suppressed by screening. To describe electron transport we formulate and solve a kinetic equation for the density matrix of electrons. The correction to the conductance G is negative and strongly enhanced in the region 0.5 × 2e 2/h ≤ G ≤ 1.0 × 2e 2/h. Our results for conductance agree with the so-called "0.7 structure" observed in experiments. © 2008 EDP Sciences/Società Italiana di Fisica/Springer-Verlag.
- Article. Terekhov Ivan S., Milstein Alexander I., Kotov Valeri N., Sushkov Oleg P. Screening of coulomb impurities in graphene // Physical Review Letters. American Physical Society. United States. - ISSN 00319007. - EISSN 10797114. We calculate exactly the vacuum polarization charge density in the field of a subcritical Coulomb impurity, Z|e|/r, in graphene. Our analysis is based on the exact electron Green's function, obtained by using the operator method, and leads to results that are exact in the parameter Zα, where α is the "fine-structure constant" of graphene. Taking into account also electron-electron interactions in the Hartree approximation, we solve the problem self-consistently in the subcritical regime, where the impurity has an effective charge Zeff, determined by the localized induced charge. We find that an impurity with bare charge Z=1 remains subcritical, Zeffα<1/2, for any α, while impurities with Z=2, 3 and higher can become supercritical at certain values of α. © 2008 The American Physical Society.
- Article. Dmitriev V. F., Milstein A. I., Strakhovenko V. M. Spin effects in p over(p, ̄) interaction and their possible use to polarize antiproton beams // Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. Elsevier BV. Netherlands. - P.1122-1126. - ISSN 0168583X. The polarization buildup in a p over(p, ̄) beam which is due to the interaction of stored antiprotons with polarized protons of a hydrogen target is considered. The corresponding cross section is calculated using the Paris nucleon-antinucleon optical potential in the energy interval 20 < Tlab < 100 MeV. It follows from this estimate that, at realistic parameters of a storage ring and a target, the filtering mechanism can provide a noticeable polarization in a time comparable with the beam lifetime. © 2008 Elsevier B.V. All rights reserved.
- Article. Di Piazza A., Milstein A. I. Delbrück scattering in combined Coulomb and laser fields // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. We study Delbrück scattering in a Coulomb field in the presence of a laser field. The amplitudes are calculated in the Born approximation with respect to the Coulomb field and exactly in the parameters of the laser field having arbitrary strength, spectral content, and polarization. The case of high initial photon energy is investigated in detail for a monochromatic circularly polarized laser field. It is shown that the angular distribution of the process substantially differs from that for Delbrück scattering in a pure Coulomb field. The value of the cross section under discussion may exceed the latter at realistic laser parameters that essentially simplify the possibility of the experimental observation of the phenomenon. The effect of high order terms in the quantum intensity parameter χ of the laser field is found to be very important already at relatively small χ. © 2008 The American Physical Society.
- ConferencePaper. Sloggett C., Milstein A. I., Sushkov O. P. Electron correlations and the conductance of a quantum point contact at finite temperature // To describe electron transport through a quantum point contact we formulate and solve a nonlocal kinetic equation for the density matrix of electrons. The electron-electron interaction is treated by perturbation theory with account of higher order terms. At zero temperature, the approach results in the Landauer formula for conductance of a quantum point contact. At finite temperature, the leading correction to the current of correlated electrons scales as temperature squared. The corresponding correction to conductance G is negative and strongly enhanced in the region 0.52e2h≤G≤1.02e2h. The effect may be relevant to the so called "0.7 structure" of conductance observed experimentally. © 2008 American Institute of Physics.
- Article. Milstein Alexander I., Sushkov Oleg P. Effective action, magnetic excitations, and quantum fluctuations in lightly doped single-layer cuprates // Physical Review B - Condensed Matter and Materials Physics. American Physical Society. United States. - ISSN 10980121. We consider the extended two-dimensional t- t′ - t″ -J model at zero temperature. Parameters of the model corresponds to doping by holes. Using the low doping effective action, we demonstrate that the system can: (1) preserve the long-range collinear antiferromagnetic order, (2) lead to a spin spiral state (static or dynamic), and (3) lead to the phase-separation instability. We show that at parameters of the effective action corresponding to the single-layer cuprate La2-x Srx CuO4, the spin spiral ground state is realized. We derive properties of magnetic excitations and calculate quantum fluctuations. Quantum fluctuations destroy the static spin spiral at the critical doping xc ≈0.11. This is the point of the quantum phase transition to the spin-liquid state (dynamic spin spiral). The state is still double degenerate with respect to the direction of the dynamic spiral, so this is a "directional nematic." The superconducting pairing exists throughout the phase diagram and is not sensitive to the quantum phase transition. We also compare the calculated neutron-scattering spectra with experimental data. © 2008 The American Physical Society.
- Article. Milstein A. I., Salnikov S. G., Strakhovenko V. M. Polarization effects in non-relativistic ep scattering // Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. Elsevier BV. Netherlands. - P.3453-3457. - ISSN 0168583X. The cross section which addresses the spin-flip transitions of a proton (antiproton) interacting with a polarized non-relativistic electron or positron is calculated analytically. In the case of attraction, this cross section is greatly enhanced for sufficiently small relative velocities as compared to the result obtained in the Born approximation. However, it is still very small, so that the beam polarization time turns out to be enormously large for the parameters of e± beams available now. This practically rules out a use of such beams to polarize stored antiprotons or protons. © 2008 Elsevier B.V. All rights reserved.
- Article. Dmitriev V. F., Milstein A. I. Constraints on N over(N, ̄) interaction from the process e+ e- → N over(N, ̄) near threshold // Nuclear Physics B - Proceedings Supplements. North-Holland Publ Co. Netherlands. - P.66-70. - ISSN 09205632. We use the Paris nucleon-antinucleon optical potential for explanation of experimental data in the process e+ e- → p over(p, ̄) near threshold. It is shown that the cross section and the electromagnetic form factors are very sensitive to the parameters of the potential. We use the data to obtain bounds on the absorptive part of the potential in the channel with J = S = 1. © 2008 Elsevier B.V. All rights reserved.
- Article. Lee R. N., Milstein A. I. Correction to Molière's formula for multiple scattering // Journal of Experimental and Theoretical Physics. Maik Nauka/Interperiodica Publishing. Russian Federation. - P.977-979. - ISSN 10637761. - EISSN 10906509. The semiclassical correction to Molière's formula for multiple scattering is derived. The consideration is based on the scattering amplitude obtained with the first semiclassical correction taken into account for an arbitrary localized but not spherically symmetric potential. Unlike the leading term, the correction to Molière's formula contains the target density n and thickness L not only in the combination nL (areal density). Therefore, this correction can be referred to as the bulk density correction. It turns out that the bulk density correction is small even for high density. This result explains the wide range of applicability of Molière's formula. © 2009 Pleiades Publishing, Ltd.
- Article. Jackiw R., Milstein A. I., Pi S. Y., Terekhov I. S. Induced current and Aharonov-Bohm effect in graphene // Physical Review B - Condensed Matter and Materials Physics. American Physical Society. United States. - ISSN 10980121. The effect of vacuum polarization in the field of an infinitesimally thin solenoid at distances much larger than the radius of solenoid is investigated. The induced charge density and induced current are calculated. Though the induced charge density turned out to be zero, the induced current is a finite periodical function of the magnetic flux Φ. The expression for this function is found exactly in a value of the flux. The induced current is equal to zero at the integer values of Φ/ Φ0 as well as at half-integer values of this ratio, where Φ0 =2πc/e is the elementary magnetic flux. The latter is a consequence of the Furry theorem and periodicity of the induced current with respect to magnetic flux. As an example we consider the graphene in the field of solenoid perpendicular to the plane of a sample. © 2009 The American Physical Society.
- Article. Di Piazza A., Lötstedt E., Milstein A. I., Keitel C. H. Barrier control in tunneling e+-e-photoproduction // Physical Review Letters. American Physical Society. United States. - ISSN 00319007. - EISSN 10797114. Tunneling electron-positron pair production is studied in a new setup in which a strong low-frequency and a weak high-frequency laser field propagate in the same direction and collide head-on with a relativistic nucleus. The electron-positron pair-production rate is calculated analytically in the limit in which in the nucleus rest frame, the strong field is undercritical and the frequency of the weak field is below and close to the pair-production threshold. By changing the frequency of the weak field, one can reduce the tunneling barrier substantially. As a result, tunneling pair production is shown to be observable with presently available technology. © 2009 The American Physical Society.
- Article. Lee R. N., Milstein A. I. Strong suppression of Coulomb corrections to the e+e- pair production cross section in ultrarelativistic nuclear collisions // Journal of Experimental and Theoretical Physics. Maik Nauka/Interperiodica Publishing. Russian Federation. - P.968-972. - ISSN 10637761. - EISSN 10906509. The Coulomb corrections to the e+e- pair production cross section in ultrarelativistic nuclear collisions are calculated in the next-to-leading approximation with respect to the parameter L = lnγAγB, where γA, B are the Lorentz factors of colliding nuclei. We find considerable reduction of the Coulomb corrections even for large γAγB due to the suppression of the e+e- pair production with the total energy of the order of a few electron masses in the rest frame of one of the nuclei. Our result explains why the deviation from the Born result was not observed in the SPS experiment [1, 2]. © Pleiades Publishing, Inc., 2009.
- Article. Milstein Alexander I., Terekhov Ivan S. Induced charge generated by a potential well in graphene // Physical Review B - Condensed Matter and Materials Physics. American Physical Society. United States. - ISSN 10980121. The induced charge density, ρind (r), generated in graphene by the potential well of the finite radius R is considered. The result for ρind (r) is derived for large distances rR. We also obtained the induced charges outside of the radius rR and inside of this radius for subcritical and supercritical regimes. The consideration is based on the convenient representation of the induced charge density via the Green's function of electron in the field. © 2010 The American Physical Society.
- Article. Di Piazza A., Lötstedt E., Milstein A. I., Keitel C. H. Effect of a strong laser field on electron-positron photoproduction by relativistic nuclei // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. We study the influence of a strong laser field on the Bethe-Heitler photoproduction process by a relativistic nucleus. The laser field propagates in the same direction as the incoming high-energy photon, and it is taken into account exactly in the calculations. Two cases are considered in detail. In the first case, the energy of the incoming photon in the nucleus rest frame is much larger than the electron's rest energy. The presence of the laser field may significantly suppress the photoproduction rate at soon-available values of laser parameters. In the second case, the energy of the incoming photon in the rest frame of the nucleus is less than and close to the electron-positron pair-production threshold. The presence of the laser field allows for the pair-production process, and the obtained electron-positron rate is much larger than in the presence of only the laser and the nuclear field. In both cases, we have observed a strong dependence of the rate on the mutual polarization of the laser field and on the high-energy photon, and the most favorable configuration is with laser field and high-energy photon linearly polarized in the same direction. The effects discussed are, in principle, measurable with presently available proton accelerators and laser technology. © 2010 The American Physical Society.
- Article. Dmitriev V. F., Milstein A. I., Salnikov S. G. Spin-dependent part of p over(p, -) interaction cross section and Nijmegen potential // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.427-430. - ISSN 03702693. Low energy p over(p, ̄) interaction is considered taking into account the polarization of both particles. The corresponding cross sections are calculated using the Nijmegen nucleon-antinucleon optical potential. Then they are applied to the analysis of the polarization buildup which is due to the interaction of stored antiprotons with polarized protons of a hydrogen target. It is shown that, at realistic parameters of a storage ring and a target, the filtering mechanism may provide a noticeable polarization in a time comparable with the beam lifetime. © 2010 Elsevier B.V. All rights reserved.
- Article. Anashin V. V., Aulchenko V. M., Baldin E. M., Barladyan A. K., Barónyakov A. Yu, Barónyakov M. Yu, Baru S. E., Bedny I. V., Beloborodova O. L., Blinov A. E., Blinov V. E., Bobrov A. V., Bobrovnikov V. S., Bogomyagkov A. V., Bondar A. E., Buzykaev A. R., Eidelman S. I., Glukhovchenko Yu M., Gulevich V. V., Gusev D. V., Karnaev S. E., Karpov G. V., Karpov S. V., Kharlamova T. A., Kiselev V. A., Kononov S. A., Kotov K. Yu, Kravchenko E. A., Kulikov V. F., Kurkin G. Ya, Kuper E. A., Levichev E. B., Maksimov D. A., Malyshev V. M., Maslennikov A. L., Medvedko A. S., Meshkov O. I., Milstein A. I., Mishnev S. I., Morozov I. I., Muchnoi N. Yu, Neufeld V. V., Nikitin S. A., Nikolaev I. B., Okunev I. N., Onuchin A. P., Oreshkin S. B., Orlov I. O., Osipov A. A., Peleganchuk S. V., Pivovarov S. G., Piminov P. A., Petrov V. V., Poluektov A. O., Popkov I. N., Pospelov G. E., Prisekin V. G., Ruban A. A., Sandyrev V. K., Savinov G. A., Shamov A. G., Shatilov D. N., Shwartz B. A., Simonov E. A., Sinyatkin S. V., Skovpen Yu I., Skrinsky A. N., Smaluk V. V., Sokolov A. V., Sukharev A. M., Starostina E. V., Talyshev A. A. Measurement of J/ψ → ηcγ at KEDR // Chinese Physics C. Institute of Physics Publishing. United Kingdom. - P.831-835. - ISSN 16741137. We present a study of the inclusive photon spectra from 5.9 million J/ψ decays collected with the KEDR detector at the VEPP-4M e+e - collider. We measure the branching fraction of radiative decay J/ψ ηcγ, ηc width and mass. Our preliminary results are: M(ηc) 2979.4±1.5±1.9 MeV/c2, Γ(ηc) = 27.8±5.1±3.3 MeV, Γ(J/ψ → ηcγ) = (2.34±0.15±0. 40)%. © 2010 Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Sciences and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.
- Article. Di Piazza A., Milstein A. I. High-energy electron-positron photoproduction cross section close to the end of the spectrum // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. We consider the cross section of electron-positron pair production by a high-energy photon in a strong Coulomb field close to the end of the electron or positron spectrum. We show that the cross section essentially differs from the result obtained in the Born approximation as well as from the result which takes into account the Coulomb corrections under the assumption that both electron and positron are ultrarelativistic. The cross section of bremsstrahlung in a strong Coulomb field by a high-energy electron is also obtained in the region where the final electron is not ultrarelativistic. © 2010 The American Physical Society.
- Article. Di Piazza A., Milstein A. I., Müller C. Polarization of the electron and positron produced in combined Coulomb and strong laser fields // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. The process of e+e- production in the superposition of a Coulomb and a strong laser field is considered. The pair production rate integrated over the momentum and summed over the spin projections of one of the particles is derived exactly in the parameters of the laser field and in the Born approximation with respect to the Coulomb field. The case of a monochromatic circularly polarized laser field is considered in detail. A very compact analytical expression of the pair production rate and its dependence on the polarization of one of the created particles is obtained in the quasiclassical approximation for the experimentally relevant case of an undercritical laser field. As a result, the polarization of the created electron (positron) is derived. © 2010 The American Physical Society.
- Article. Milstein Alexander I., Terekhov Ivan S. Induced current in the presence of a magnetic flux tube of small radius // Physical Review B - Condensed Matter and Materials Physics. American Physical Society. United States. - ISSN 10980121. The induced current density, corresponding to the massless Dirac equation in (2+1) dimensions in a magnetic flux tube of small radius is considered. This problem is important for graphene. In the case when an electron cannot penetrate the region of nonzero magnetic field, this current is the odd periodical function of the magnetic flux. If the region inside the magnetic tube is not forbidden for penetration of electron, the induced current is not a periodical function of the magnetic flux. However, in the limit R→0, where R is the radius of the magnetic flux tube, this function has the universal form which is independent of the magnetic field distribution inside the magnetic tube at fixed value of the magnetic flux. © 2011 American Physical Society.
- Article. Bondar A. E., Dmitriev V. F., Milstein A. I., Strakhovenko V. M. Nucleon polarization in the process e +e -→NN̄ near threshold // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.159-163. - ISSN 03702693. The process e +e -→NN̄ is studied nearby a threshold with account for polarizations of all initial and final particles. The nucleon polarization ζN reveals a strong energy dependence due to that of the nucleon electromagnetic form factors GE(Q2) and GM(Q2) caused by the final-state interaction of nucleons. It is shown that the modulus of the ratio of these form factors and their relative phase can be determined by measuring ζN along with the differential cross section. The polarization degree is analyzed using Paris NN̄ optical potential for calculation of the form factors. It turns out that |ζN| is high enough in a rather wide energy range above the threshold. Being especially high for longitudinally polarized beams, |ζN| is noticeable even if both e +e - beams are unpolarized. © 2011 Elsevier B.V.
- ConferencePaper. Dmitriev V. F., Milstein A. I., Salnikov S. G. Spin-dependent part of pp̄ interaction cross section and Nijmegen potential // Journal of Physics: Conference Series. Institute of Physics. United Kingdom. - ISSN 17426588. Low energy pp̄ interaction is considered taking into account the polarization of both particles. The corresponding cross sections are calculated using the Nijmegen nucleon-antinucleon optical potential. Then they are applied to the analysis of the polarization buildup which is due to the interaction of stored antiprotons with polarized protons of a hydrogen target. It is shown that, at realistic parameters of a storage ring and a target, the filtering mechanism may provide a noticeable beam polarization in a time comparable with the beam lifetime.
- Article. Lee R. N., Milstein A. I., Terekhov I. S. Relativistic Coulomb Green's function in d dimensions // Journal of Experimental and Theoretical Physics. Maik Nauka/Interperiodica Publishing. Russian Federation. - P.202-206. - ISSN 10637761. - EISSN 10906509. Using the operator method, we derive the Green's functions of the Dirac and Klein-Gordon equations in the Coulomb potential-Zα/r for an arbitrary space dimensionality d. Nonrelativistic and semiclassical asymptotic forms of these Green's functions are considered in detail. © 2011 Pleiades Publishing, Ltd.
- Article. Bondar A. E., Garmash A., Milstein A. I., Mizuk R., Voloshin M. B. Heavy quark spin structure in Zb resonances // Physical Review D - Particles, Fields, Gravitation and Cosmology. American Physical Society. United States. - ISSN 15507998. We discuss the heavy quark spin structure of the recently observed "twin" resonances Zb(10610) and Zb(10650), assuming that these are mostly of a "molecular" type, i.e. that their internal dynamics is dominated by the coupling to meson pairs B *B̄-BB̄* and B *B̄*. We find that the state of the bb̄ pair within the Zb(10610) and Zb(10650) resonances is a mixture of a spin-triplet and a spin-singlet of equal amplitude and with the phase orthogonal between the two resonances. Such a structure gives rise to specific relations between observable amplitudes that are in agreement with the data obtained recently by Belle. We also briefly discuss possible properties of the isotopically singlet counterparts of the newly found resonances, and also of their C (G) parity opposites that likely exist in the same mass range near the open B flavor threshold. © 2011 American Physical Society.
- Article. Milstein Alexander I., Sushkov Oleg P. Effective field theories and spin-wave excitations in helical magnets // Physical Review B - Condensed Matter and Materials Physics. American Physical Society. United States. - ISSN 10980121. We consider two classes of helical magnets. The first class has magnetic ordering close to that of an antiferromagnet and the second class has magnetic ordering close to that of a ferromagnet. The first case is relevant to cuprate superconductors and the second case is realized in FeSrO 3 and FeCaO 3. We derive the effective field theories for these cases and calculate the corresponding excitation spectra. We demonstrate that the "hourglass" spin-wave dispersion observed experimentally in the cuprates is a fingerprint of the "antiferromagnetic spin spiral state." We also show that quantum fluctuations are important for the "ferromagnetic spin spiral," as they influence qualitative features of the spin-wave dispersion. © 2011 American Physical Society.
- Article. Lee R. N., Milstein A. I., Strakhovenko V. M. Charge asymmetry in the differential cross section of high-energy e +e - photoproduction in the field of a heavy atom // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. Quasiclassical correction to the differential cross section of high-energy electron-positron photoproduction in the electric field of a heavy atom is obtained with the exact account of the field. This correction is responsible for the charge asymmetry A in this process. When the transverse momentum of at least one of the produced particles is much larger than the electron mass m, the charge asymmetry can be as large as tens percent. We also estimate the contribution A to the charge asymmetry coming from the Compton-type diagram. For heavy nuclei, this contribution is negligible. For light nuclei, A is noticeable only when the angle between the momenta of the electron and positron is of order of m/ω (ω is the photon energy) while the transverse momenta of both particles are much larger than m. © 2012 American Physical Society.
- Article. Di Piazza A., Milstein A. I. Angular distribution of high-energy e +e - photoproduction close to the end of the spectrum at large momentum transfer // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. We consider the differential cross section of electron-positron pair production by a high-energy photon in a strong Coulomb field close to the end of the electron or positron spectrum. When the momentum transfer Q largely exceeds the electron mass, the cross section is obtained analytically in a compact form, and it is proportional to 1/Q4. Coulomb corrections essentially modify the cross section even for moderate values of the nuclear charge number Z. In the same kinematical region, the angular distribution for bound-free pair production, bremsstrahlung, and photorecombination is also obtained. © 2012 American Physical Society.
- Article. Lee R. N., Milstein A. I., Terekhov I. S. Quasilocalized states in a model of electron-electron interaction in graphene // Physical Review B - Condensed Matter and Materials Physics. American Physical Society. United States. - ISSN 10980121. A quantum mechanical model of two interacting electrons in graphene is considered. We concentrate on the case of zero total momentum of the pair. We show that the dynamics of the system is very unusual. Both stationary and time-dependent problems are considered. It is shown that the complete set of wave functions with definite energy includes new functions that were previously overlooked. The time evolution of the wave packet, corresponding to the scattering problem setup, leads to the appearance of a localized state at large time. The asymptotics of this state is found analytically. We obtain the lower bound of the lifetime of this state, which is connected with the breakdown of the continuous model on the lattice scale. The estimate of this bound gives one hope to observe the localized states experimentally. © 2012 American Physical Society.
- Article. Di Piazza A., Milstein A. I. Quasiclassical approach to high-energy QED processes in strong laser and atomic fields // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.224-228. - ISSN 03702693. An approach, based on the use of the quasiclassical Green's function, is developed for investigating high-energy quantum electrodynamical processes in combined strong laser and atomic fields. Employing an operator technique, we derive the Green's function of the Dirac equation in an arbitrary plane wave and a localized potential. Then, we calculate the total cross section of high-energy electron-positron photoproduction in an atomic field of arbitrary charge number (Bethe-Heitler process) in the presence of a strong laser field. It is shown that the laser field substantially modifies the cross section at already available incoming photon energies and laser parameters. This makes it feasible in principle to observe with present technology the analogous effect in a laser field of the Landau-Pomeranchuk-Migdal effect for the Bethe-Heitler process. © 2012 Elsevier B.V.
- Article. Dmitriev V. F., Milstein A. I. Final state Coulomb interaction and asymmetry of pair production close to threshold in e+e- annihilation // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.83-85. - ISSN 03702693. We investigate a contribution of the d wave to the cross section of e+e- annihilation to the pair of charged leptons or nucleons close to the threshold of the process. In contrast to the point of view accepted in literature, due to the Coulomb final state interaction this contribution does not vanish even at zero relative velocity of produced particles. This results in the nonzero asymmetry in angular distribution at the threshold. Though value of the asymmetry is small, observation of this effect is not hopeless. © 2013 Elsevier B.V.
- Article. Sushkov O. P., Milstein A. I., Mori M., Maekawa S. Relativistic effects in scattering of polarized electrons // Europhysics Letters. EDP Sciences. France. - ISSN 02955075. - EISSN 12864854. The right-left asymmetry (skew scattering) and the side jump effect are manifestations of the spin-orbit interaction in scattering of polarized electrons. While the side jump effect is less known than the right-left asymmetry, the effect is of conceptual importance for generic spin-orbital physics, and the effect is widely discussed in spintronics. We reexamine the side jump effect accounting for the exact nonperturbative electron wave function inside the atom/impurity/host atomic core. We find that the size of the effect is much smaller than estimates accepted in the literature. The reduction factor is 1/Z2, where Z is the nuclear charge. This implies that the side jump effect is practically irrelevant, the skew scattering and/or the intrinsic mechanism always dominate the transverse deflection of the electron beam and hence dominate the anomalous Hall and spin Hall effects. © Copyright EPLA, 2013.
- Article. Milstein A. I., Salnikov S. G. Kinetics of polarization in non-relativistic scattering // Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. Elsevier BV. Netherlands. - P.64-67. - ISSN 0168583X. An approach is developed, which essentially simplifies the derivation of the kinetic equation for polarization in non-relativistic scattering. This approach is applicable for collisions of projectile particles with a target for any spin of the colliding particles. A detailed consideration is performed for the case of spin 1/2 projectile particles interacting with spin 1/2 particle of a target. The solution of the kinetic equation for the case of zero initial polarization is presented as well. © 2013 Elsevier B.V. All rights reserved.
- Article. Dmitriev V. F., Milstein A. I., Salnikov S. G. Isoscalar amplitude dominance in e+e−annihilation to NN̄ pair close to the threshold // Physics of Atomic Nuclei. Maik Nauka/Interperiodica Publishing. Russian Federation. - P.1173-1177. - ISSN 10637788. - EISSN 1562692X. © 2014, Pleiades Publishing, Ltd. We use the Paris nucleon-antinucleon optical potential for explanation of experimental data in the process e+e− → pp̄ near threshold. It turns out that final-state interaction due to Paris optical potential allows us to reproduce available experimental data. It follows from our consideration that the isoscalar form factor is much larger than the isovector one.
- Article. Downie E. J., Lee R. N., Milstein A. I., Ron G. Charge asymmetry in high-energy μ+μ- photoproduction in the electric field of a heavy atom // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.645-649. - ISSN 03702693. The charge asymmetry in the differential cross section of high-energy μ+μ- photoproduction in the electric field of a heavy atom is obtained. This asymmetry arises due to the Coulomb corrections to the amplitude of the process (next-to-leading term with respect to the atomic field). The deviation of the nuclear electric field from the Coulomb field at small distances is crucially important for the charge asymmetry. Though the Coulomb corrections to the total cross section are negligibly small, the charge asymmetry is measurable for selected final states of μ+ and μ-. We further discuss the feasibility for experimental observation of this effect. © 2013 The Authors. Published by Elsevier B.V.
- Article. Di Piazza A., Milstein A. I. Ultrarelativistic quasiclassical wave functions in strong laser and atomic fields // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. The problem of an ultrarelativistic charge in the presence of an atomic and a plane-wave field is investigated in the quasiclassical regime by including exactly the effects of both fields. Starting from the quasiclassical Green's function obtained by Di Piazza and Milstein [Phys. Lett. B 717, 224 (2012)PYLBAJ0370-269310.1016/j.physletb.2012.09.043], the corresponding in- and out-wave functions are derived in the experimentally relevant case of the plane wave counterpropagating with respect to the initial momentum of the particle. The knowledge of these electron wave functions opens the possibility of investigating a variety of problems in strong-field QED, where both the atomic field and the laser field are strong enough to be taken into account exactly from the beginning in the calculations. © 2014 American Physical Society.
- Article. Krachkov P. A., Lee R. N., Milstein A. I. High-energy e+e- photoproduction in the field of a heavy atom accompanied by bremsstrahlung // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. © 2014 American Physical Society. Helicity amplitudes and the differential cross section of high-energy e+e- photoproduction accompanied by bremsstrahlung in the electric field of a heavy atom (i.e., the amplitudes of the process γ1Z→e+e-γ2Z) are derived. The results are exact in the nuclear charge number and are obtained in the leading quasiclassical approximation. They correspond to the leading high-energy small-angle asymptotics of the amplitude. It is shown that, in general, accounting for the Coulomb corrections essentially modify the differential cross section, which is different from the Born result. When the initial photon is circularly polarized, the Coulomb corrections lead to the asymmetry in the distribution over the azimuth angles φi of produced particles with respect to the replacement φi→-φi.
- Article. Krachkov P. A., Milstein A. I. Charge asymmetry in the differential cross section of high-energy bremsstrahlung in the field of a heavy atom // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. © 2015 American Physical Society. The distinction between the charged particle and antiparticle differential cross sections of high-energy bremsstrahlung in the electric field of a heavy atom is investigated. The consideration is based on the quasiclassical approximation to the wave functions in the external field. The charge asymmetry (the ratio of the antisymmetric and symmetric parts of the differential cross section) arises due to the account for the first quasiclassical correction to the differential cross section. All evaluations are performed with the exact account of the atomic field. We consider in detail the charge asymmetry for electrons and muons. For electrons, the nuclear size effect is not important while for muons this effect should be taken into account. For the longitudinal polarization of the initial charged particle, the account for the first quasiclassical correction to the differential cross section leads to the asymmetry in the cross section with respect to the replacement φ→-φ, where φ is the azimuth angle between the photon momentum and the momentum of the final charged particle.
- Article. Milstein Alexander I., Sushkov Oleg P. Magnetic excitations in the spin-spiral state of TbMnO3 and DyMnO3 // Physical Review B - Condensed Matter and Materials Physics. American Physical Society. United States. - ISSN 10980121. © 2015 American Physical Society. We calculate spectra of magnetic excitations in the spin-spiral state of perovskite manganates. The spectra consist of several branches corresponding to different polarizations and different ways of diffraction from the static magnetic order. The easy-axis crystal-field anisotropy and the Dzyaloshinski-Moriya anisotropy lead to opening of gaps in Goldstone modes and to discontinuities in magnon dispersions. Comparing results of the calculation with available experimental data, we determine values of effective exchange parameters and anisotropies. To simplify calculations and to get a clearer physical insight into the structure of excitations, we use the σ-model-like effective-field theory instead of the conventional spin-wave approach to analyze the Heisenberg Hamiltonian and to derive the spectra.
- Article. Krachkov P. A., Lee R. N., Milstein A. I. Double bremsstrahlung from high-energy electrons in an atomic field // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - ISSN 10941622. © 2015 American Physical Society. © 2015 American Physical Society. The differential cross section of double bremsstrahlung (emission of two photons) from high-energy electron in the electric field of heavy atoms is derived. The results are obtained with the exact account of the atomic field by means of the quasiclassical approximation to the wave functions and the Green's function in the external field. It is shown that the Coulomb corrections to the differential cross section (the difference between the exact result and the result obtained in the leading Born approximation) correspond to small momentum transfers. The Coulomb corrections to the differential cross section of double bremsstrahlung are accumulated in the factor, which coincides with the corresponding factor in the differential cross section of single bremsstrahlung. At small momentum transfer, the Coulomb corrections to the differential cross section are very sensitive to the parameters of screening while the Coulomb corrections to the cross section integrated over the momentum transfer have the universal form.
- Review. Krachkov P. A., Lee R. N., Milstein A. I. Quantum electrodynamics processes in the interaction of high-energy particles with atoms // Physics Uspekhi. Russian Academy of Sciences. Russian Federation. - P.619-641. - ISSN 10637869. - EISSN 14684780. © 2016 Uspekhi Fizicheskikh Nauk, Russian Academy of Sciences.The recently developed method of quasiclassical Green's functions of the Dirac equation in the variously configured external fields has provided breakthrough insight into fundamental quantum electrodynamics processes whereby high-energy particles interact with atoms. This paper reviews latest calculated results, exact in the atomic field parameters, on the cross sections for electron-positron high-energy photo-production, the single bremsstrahlung cross section for relativistic electrons and muons in an atomic field, double bremsstrahlung cross sections, etc. In many cases, the calculations are performed in the quasiclassical approximation with the inclusion of the first-order quasiclassical correction.
- Article. Dmitriev V. F., Milstein A. I., Salnikov S. G. Real and virtual N N ¯ pair production near the threshold REAL and VIRTUAL N N ¯ PAIR PRODUCTION NEAR ⋯ V. F. DMITRIEV, A. I. MILSTEIN, and S. G. SALNIKOV // Physical Review D - Particles, Fields, Gravitation and Cosmology. American Physical Society. United States. - ISSN 15507998. © 2016 American Physical Society. Nucleon-antinucleon optical potential, which explains the experimental data for the processes e+e-→pp¯ and e+e-→pions near the threshold of pp¯ pair production, is suggested. To obtain this potential, we have used the available experimental data for pp¯ scattering, pp¯ pair production in e+e- annihilation, and the ratio of electromagnetic form factors of a proton in the timelike region. It turns out that final-state interaction via the optical potential allows one to reproduce the available experimental data with good accuracy. Our results for the cross sections of the e+e-→6π process near the threshold of pp¯ pair production are in agreement with the recent experiments.
- Article. Krachkov P. A., Milstein A. I. High-energy electroproduction in an atomic field // Physical Review A - Atomic, Molecular, and Optical Physics. American Physical Society. United States. - P.. - ISSN 10941622. © 2016 American Physical Society.The differential cross section of high-energy electroproduction in the electric field of heavy atoms is derived. The results are obtained with the exact account for the atomic field. We use the quasiclassical approximation to the wave functions in the external field. For heavy atoms, the Coulomb corrections substantially modify the differential cross section as compared with the Born result. They lead to the azimuth asymmetry in the differential cross section for the polarized incoming electron. The Coulomb corrections to the total cross section are obtained in the leading logarithmic approximation.
- Article. Dmitriev V. F., Milstein A. I., Salnikov S. G. Angular distributions in [formula presented] decays // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.139-142. - ISSN 03702693. © 2016 The Author(s)The differential decay rates of the processes J/ψ→pp¯π0 and J/ψ→pp¯η close to the pp¯ threshold are calculated with the help of the NN¯ optical potential. The same calculations are made for the decays of ψ(2S). We use the potential which has been suggested to fit the cross sections of NN¯ scattering together with NN¯ and six pion production in e+e− annihilation close to the pp¯ threshold. The pp¯ invariant mass spectrum is in agreement with the available experimental data. The anisotropy of the angular distributions, which appears due to the tensor forces in the NN¯ interaction, is predicted close to the pp¯ threshold. This anisotropy is large enough to be investigated experimentally. Such measurements would allow one to check the accuracy of the model of NN¯ interaction.
- Article. Lee R. N., Milstein A. I. Electron–positron pair production in ion collisions at low velocity beyond Born approximation // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. Elsevier BV. Netherlands. - P.340-343. - ISSN 03702693. © 2016 The Author(s)We derive the spectrum and the total cross section of electromagnetic e+e− pair production in the collisions of two nuclei at low relative velocity β. Both free–free and bound-free e+e− pair production is considered. The parameters ηA,B=ZA,Bα are assumed to be small compared to unity but arbitrary compared to β (ZA,B are the charge numbers of the nuclei and α is the fine structure constant). Due to a suppression of the Born term by high power of β, the first Coulomb correction to the amplitude appears to be important at ηA,B≳β. The effect of a finite nuclear mass is discussed. In contrast to the result obtained in the infinite nuclear mass limit, the terms ∝M−2 are not suppressed by the high power of β and may easily dominate at sufficiently small velocities.
- Article. Kotelnikov Igor A., Milstein Alexander I. Electron radiative recombination with a hydrogen-like ion // Physica Scripta. Royal Swedish Academy of Sciences. Sweden. - P.. - ISSN 00318949. © 2019 IOP Publishing Ltd. We survey the results of a long-term study of the process of radiative recombination (RR). A rigorous theory of non-relativistic electron RR with a hydrogen-like ion is used to calculate the total cross section of the process, the effective radiation, the recombination rate coefficient, and the emission coefficient in a plasma with a Maxwellian electron distribution. The exact results are compared with the numerous known asymptotic and interpolation formulas. We propose interpolation formulas which ensure a uniform approximation of all mentioned quantities in a wide range of plasma temperatures.