Measurements of baryon pair decays of chi(cJ) mesons

Abstract

Using 106 x 10(6) psi' decays collected with the BESIII detector at the BEPCII, three decays of chi(cJ) (J = 0, 1, 2) with baryon pairs (Lambda(Lambda) over bar, Sigma(0)(Sigma) over bar (0),Sigma(+)(Sigma) over bar (-)) in the final state have been studied. The branching fractions are measured to be B(chi(c0,1,2) -> Lambda(Lambda) over bar) = (33.3 +/- 2.0 +/- 2.6) x 10(-5), (12.2 +/- 1.1 +/- 1.1) x 10(-5), (20.8 +/- 1.6 +/- 2.3) x 10(-5), B(chi(c0,1,2) -> Sigma(0)(Sigma) over bar (0)) = (47.8 +/- 3.4 +/- 3.9) x 10(-5), (3.8 +/- 1.0 +/- 0.5) x 10(-5), (4.0 +/- 1.1 +/- 0.5) x 10(-5), and B(chi(c0,1,2) -> Sigma(+)(Sigma) over bar (-)) = (45.4 +/- 4.2 +/- 3.0) x 10(-5), (5.4 +/- 1.5 +/- 0.5) x 10(-5), (4.9 +/- 1.9 +/- 0.7) x 10(-5), where the first error is statistical and the second is systematic. Upper limits on the branching fractions for the decays of chi(c1,2) -> Sigma(0)(Sigma) over bar (0), Sigma(+)(Sigma) over bar (-) are estimated to be B(chi(c1) -> Sigma(0)(Sigma) over bar (0)) 6.2 x 10(-5), B(chi(c2) -> Sigma(0)<(Sigma) over bar (0)) 6.5 x 10(-5), B(chi(c1) -> Sigma(+)<(Sigma) over bar (-)) 8.7 x 10(-5) and B(chi(c2) -> Sigma(+)<(Sigma) over bar (-)) < 8.8 x 10(-5) at the 90% confidence level.