ISSN - 01709739, Zeitschrift f�r Physik C-Particles and Fields, 1992, vol. 53, p. 219-224
Total cross section of two-photon production of hadrons
The total cross section for γγ→hadrons was measured as a function of the invariant mass W of the system (1.25 to 4.25 GeV) at the e+e--collider VEPP-4 with the detector MD-1. For the first time the data were obtained by detecting both scattered leptons with almost zero emission angles. The mean squared four momentum transfer 〈q2〉 is -0.005 GeV2, the rms W resolution is 100-250 MeV. The data on the mean charged multiplicity 〈nC〉 are well described by the function 〈nC〉=(1.62 ±0.37)+(1.83±0.45)·ln(W(GeV)). The W dependence of the total cross section is consistent with the theoretical prediction σ(nb)=240+270/W(GeV). © 1992 Springer-Verlag.