Вы находитесь на старом сайте НГУ. Перейти на новый сайт

ISSN - 00319007, EISSN - 10797114, Physical Review Letters, 2005, vol. 95, p. -

Observation of a broad structure in the n+n-J/ψ mass spectrum around 4.26GeV/c2

Aubert B., Barate R., Boutigny D., Couderc F., Karyotakis Y., Lees J. P., Poireau V., Tisserand V., Zghiche A., Grauges E., Palano A., Pappagallo M., Pompili A., Chen J. C., Qi N. D., Rong G., Wang P., Zhu Y. S., Eigen G., Ofte I., Stugu B., Abrams G. S., Battaglia M., Breon A. B., Brown D. N., Button-Shafer J., Cahn R. N., Charles E., Day C. T., Gill M. S., Gritsan A. V., Groysman Y., Jacobsen R. G., Kadel R. W., Kadyk J., Kerth L. T., Kolomensky Yu G., Kukartsev G., Lynch G., Mir L. M., Oddone P. J., Orimoto T. J., Pripstein M., Roe N. A., Ronan M. T., Wenzel W. A., Barrett M., Ford K. E., Harrison T. J., Hart A. J., Hawkes C. M., Morgan S. E., Watson A. T., Fritsch M., Goetzen K., Held T., Koch H., Lewandowski B., Pelizaeus M., Peters K., Schroeder T., Steinke M., Boyd J. T., Burke J. P., Chevalier N., Cottingham W. N., Cuhadar-Donszelmann T., Fulsom B. G., Hearty C., Knecht N. S., Mattison T. S., McKenna J. A., Khan A., Kyberd P., Saleem M., Teodorescu L., Blinov A. E., Blinov V. E., Bukin A. D., Druzhinin V. P., Golubev V. B., Kravchenko E. A., Onuchin A. P., Serednyakov S. I., Skovpen Yu I., Solodov E. P., Yushkov A. N., Best D., Bondioli M., Bruinsma M., Chao M., Curry S., Eschrich I., Kirkby D., Lankford A. J., Lund P., Mandelkern M., Mommsen R. K., Roethel W.

We study initial-state radiation events, e+e- â†'ÎISRÏ€+Ï€-J/Ï, with data collected with the BABAR detector. We observe an accumulation of events near 4.26GeV/c2 in the invariant-mass spectrum of Ï€+Ï€-J/Ï. Fits to the mass spectrum indicate that a broad resonance with a mass of about 4.26GeV/c2 is required to describe the observed structure. The presence of additional narrow resonances cannot be excluded. The fitted width of the broad resonance is 50 to 90MeV/c2, depending on the fit hypothesis. © 2005 The American Physical Society.