Observation of the η c (2980) Produced in the Radiative Decay of the ψ ′ (3684)

• Published in: Physical review letters Vol. 45; no. 14; pp. 1146 - 1149
• Main Authors: Himel, T. M., Trilling, G. H., Abrams, G. S., Alam, M. S., Blocker, C. A., Blondel, A. P., Boyarski, A. M., Breidenbach, M., Burke, D. L., Carithers, W. C., Chinowsky, W., Coles, M. W., Cooper, S., Dieterle, W. E., Dillon, J. B., Dorenbosch, J., Dorfan, J. M., Eaton, M. W., Feldman, G. J., Franklin, M. E. B., Gidal, G., Goldhaber, G., Hanson, G., Hayes, K. G., Hitlin, D. G., Hollebeek, R. J., Innes, W. R., Jaros, J. A., Jenni, P., Johnson, A. D., Kadyk, J. A., Lankford, A. J., Larsen, R. R., Levi, M. E., Lüth, V., Millikan, R. E., Nelson, M. E., Pang, C. Y., Patrick, J. F., Perl, M. L., Richter, B., Roussarie, A., Scharre, D. L., Schindler, R. H., Schwitters, R. F., Siegrist, J. L., Strait, J., Taureg, H., Tonutti, M., Vella, E. N., Vidal, R. A., Videau, I., Weiss, J. M., Zaccone, H.
• Format: Journal Article
• Language: English
• Published: United States American Physical Society 01-10-1980; American Physical Society (APS)
• Subjects: High Energy Physics - Experiment; Physics; PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/PhysRevLett.45.1146

In a study of {psi}'(3684) radiative decays with the Mark II detector at SPEAR, we observe the decay sequence {psi}' {yields} {gamma}{eta}{sub c}(2980), with the {eta}{sub c}(2980) decaying into several completely reconstructed hadronic modes. We obtain a mass M = 2980 ± 8 MeV / c{sup 2} and a width {Gamma} < 40 MeV / c{sup 2} (90% confidence level), and present estimates of some of the decay branching ratios.