Вы находитесь на старом сайте НГУ. Перейти на новый сайт

ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2008, vol. 78, p. -

Measurement of the spin of the Ξ(1530) resonance

Aubert B., Bona M., Karyotakis Y., Lees J. P., Poireau V., Prudent X., Tisserand V., Zghiche A., Tico J. Garra, Grauges E., Lopez L., Palano A., Pappagallo M., Eigen G., Stugu B., Sun L., Abrams G. S., Battaglia M., Brown D. N., Button-Shafer J., Cahn R. N., Jacobsen R. G., Kadyk J. A., Kerth L. T., Kolomensky Yu G., Kukartsev G., Lynch G., Osipenkov I. L., Ronan M. T., Tackmann K., Tanabe T., Wenzel W. A., Hawkes C. M., Soni N., Watson A. T., Koch H., Schroeder T., Walker D., Asgeirsson D. J., Cuhadar-Donszelmann T., Fulsom B. G., Hearty C., Mattison T. S., McKenna J. A., Barrett M., Khan A., Saleem M., Teodorescu L., Blinov V. E., Bukin A. D., Buzykaev A. R., Druzhinin V. P., Golubev V. B., Onuchin A. P., Serednyakov S. I., Skovpen Yu I., Solodov E. P., Todyshev K. Yu, Bondioli M., Curry S., Eschrich I., Kirkby D., Lankford A. J., Lund P., Mandelkern M., Martin E. C., Stoker D. P., Abachi S., Buchanan C., Gary J. W., Liu F., Long O., Shen B. C., Vitug G. M., Yasin Z., Zhang L., Paar H. P., Rahatlou S., Sharma V., Campagnari C., Hong T. M., Kovalskyi D., Mazur M. A., Richman J. D., Beck T. W., Eisner A. M., Flacco C. J., Heusch C. A., Kroseberg J., Lockman W. S., Schalk T., Schumm B. A., Seiden A., Wilson M. G., Winstrom L. O., Chen E., Cheng C. H., Doll D. A., Echenard B., Fang F.

The properties of the Ξ(1530) resonance are investigated in the Λc+→Ξ-π+K+ decay process. The data sample was collected with the BABAR detector at the SLAC PEP-II asymmetric-energy e+e- collider operating at center-of-mass energies 10.58 and 10.54 GeV. The corresponding integrated luminosity is approximately 230fb-1. The spin of the Ξ(1530) is established to be 3/2. The existence of an S-wave amplitude in the Ξ-π+ system is inferred, and its interference with the Ξ(1530)0 amplitude provides the first clear demonstration of the Breit-Wigner phase motion expected for the Ξ(1530). The P1(cos θΞ-) Legendre polynomial moment indicates the presence of a significant S-wave amplitude for Ξ-π+ mass values above 1.6GeV/c2, and a dip in the mass distribution at approximately 1.7GeV/c2 is interpreted as due to the coherent addition of a Ξ(1690)0 contribution to this amplitude. This would imply JP=1/2- for the Ξ(1690). Attempts at fitting the Ξ(1530)0 line shape yield unsatisfactory results, and this failure is attributed to interference effects associated with the amplitudes describing the K+π+ and/or Ξ-K+ systems. © 2008 The American Physical Society.