Evidence for Λc(2593)+ production

Using the ARGUS detector at the e(+)e(-) storage ring DORIS II at DESY, we have found evidence for the production of the excited charmed baryon state Lambda c(2593)(+) in the channel Lambda(c)(+)pi(+)pi(-). Its mass was determined to be (2594.6 +/- 0.9 +/- 0.4) MeV/c(2), and the natural width measured to be Gamma = (2.9(-2.1-1.4)(+2.9+1.8)) MeV. The production cross section times thebranching ratios of sigma(e(+)e(-) --> Lambda(c)(2593)X+) x Br(Lambda(c)(2593(+)) --> Lambda(c)(+)pi(+)pi(-) ) x Br(Lambda(c)(+) --> pK(-)pi(+)) was measured to be (0.25(-0.13)(+0.24) +/- 0.13) pb. The fractions of Lambda(c)(2593)(+) decays proceeding through the Sigma(c)(0) pi(+) and Sigma(c)(++)pi(-) channels were determined to be 0.29 +/- 0.10 +/- 0.11 and 0.37 +/- 0.12 +/- 0.13, respectively. (C) 1997 Published by Elsevier Science B.V.