Measurements of branching fractions and asymmetry parameters of Xi(0)(c) -> Lambda(K)over-bar*(0), Xi(0)(c) -> Sigma(0)(K)over-bar*(0), and Xi(0)(c) -> Sigma(+) K*(-) decays at Belle
Abstrakt
Using a data sample of 980 fb(-1) collected with the Belle detector at the KEKB asymmetric-energy e(+) e(-) collider, we study the processes of Xi(0)(c) -> Lambda(K) over bar*(0), Xi(0)(c) -> Sigma(0)(K) over bar*(0), and Xi(0)(c) -> Sigma(+) K*(-) for the first time. The relative branching ratios to the normalization mode of Xi(0)(c) -> Xi(-)pi(+) are measured to be B(Xi(0)(c) -> Lambda(K) over bar*(0)/B(Xi(0)(c) -> Xi(-)pi(+)) = 0.18 +/- 0.02(stat.) +/- 0.01(syst.), B(Xi(0)(c) -> Sigma(0)(K) over bar*(0)/B(Xi(0)(c) -> Xi(-)pi(+)) = 0.69 +/- 0.03(stat.) +/- 0.03(syst.), B(Xi(0)(c) -> Sigma K+*(-)/B(Xi(0)(c) -> Xi(-)pi(+)) = 0.34 +/- 0.06(stat.) +/- 0.02(syst.), where the uncertainties are statistical and systematic, respectively.
We obtain B(Xi(0)(c) -> Lambda(K) over bar*(0)) = (3.3 +/- 0.3(stat.) +/- 0.2(syst.) +/- 1.0(ref.)) x 10(-3), B(Xi(0)(c) -> Sigma(0)(K) over bar*(0)) = (12.4 +/- 0.5(stat.) +/- 0.5(syst.) +/- 3.6(ref.)) x 10(-3), B(Xi(0)(c) -> Sigma K+*(-)) = (6.1 +/- 1.0(stat.) +/- 0.4(syst.) +/- 1.8(ref.)) x 10(-3), where the uncertainties are statistical, systematic, and from B(Xi(0)(c) -> Xi(-)pi(+)), respectively. The asymmetry parameters alpha(Xi(0)(c) -> Lambda(K) over tilde*(0)) and alpha(Xi(0)(c) -> Sigma K+*(-)) are 0.15 +/- 0.22(stat.) +/- 0.04(syst.) and -0.52 +/- 0.30(stat.) +/- 0.02(syst.), respectively, where the uncertainties are statistical followed by systematic.