Measurements of the branching fractions of Lambda(+)(c) -> p eta and Lambda(+)(c) -> p pi(0) decays at Belle

Abstract

We report measurements of the branching fractions of singly Cabibbo-suppressed decays Lambda(+)(c) -> p eta and Lambda(+)(c) -> p pi(0) using the full Belle data sample corresponding to an integrated luminosity of 980.6 fb(-1). The data were collected by the Belle detector at the KEKB e(+) e(-) asymmetric energy collidcr. A clear Lambda(+)(c) signal is seen in the invariant mass distribution of p eta. The fitted number of signal events of the Lambda(+)(c) -> p eta process is 7734 +/- 263; from this, we measure the ratio of branching fractions B(Lambda(+ )(c) -> p eta)/ B(Lambda(+)(c) -> p K- pi(+)) = [2.258 +/- 0.077(stat) +/- 0.122(syst)] x 10(-2), from which we infer the branching fraction B(Lambda(+)(c) -> p eta) = [1.42 +/- 0.05(stat) +/- 0.11(syst)] x 10(-3). In addition, no significant signal for Lambda(+)(c)-> p pi(0) is found, so an upper limit on the branching fraction of B(Lambda(+)(c) -> p eta(0)) < 8.0 x 10(-5) at a 90% credibility level is set, more than 3 times better than the best current upper limit.