Evidence for the Decay Σ+→pμ+μ-
/ Authors
H. Park, R. Burnstein, A. Chakravorty, Y. Chen, W. Choong, K. Clark, E. Dukes, C. Durandet, J. Félix, Y. Fu
and 23 more authors
G. Gidal, H. Gustafson, T. Holmstrom, M. Huang, C. James, C. Jenkins, T. Jones, D. Kaplan, L. Lederman, N. Leros, M. Longo, F. Lopez, L. Lu, W. Luebke, K. Luk, K. Nelson, J. Perroud, D. Rajaram, H. Rubin, J. Volk, C. White, S. White, P. Żyła
/ Abstract
We report the first evidence for the decay ∑+ → pμ+ μ- from data taken by the HyperCP (E871) experiment at Fermilab. Based on three observed events, the branching ratio is B(∑+ → pμ+ μ-) = [8.6 -5.4 +6.6(stat) ± 5.5(syst)] × 10 -8. The narrow range of dimuon masses may indicate that the decay proceeds via a neutral intermediate state, ∑+ rarr; pp0, p0 → μ+ μ- with a P0 mass of 214.3 ± 0.5 MeV/c 2 and branching ratio B(∑+ rarr; pp 0, p0 → μ+ μ-) = [3.1-1.9 -2.4(stat) ± 1.5(syst)] × 10 -8. © 2005 The American Physical Society.
Journal: Physical Review Letters