Measurements of branching fractions and asymmetry parameters of Ξc0→Λ^K¯∗0 , Ξc0→^{Σ0 K¯∗0} , and Ξc0→^{Σ+ K∗−} decays

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 Ξc0→ΛK¯∗0, Ξc0→Σ0K¯∗0, and Ξc0→Σ+K∗− for the first time. The relative branching ratios to the normalization mode of Ξc0→Ξ−π+ are measured to beB(Ξc0→ΛK¯∗0)/B(Ξc0→Ξ−π+)=0.18±0.02(stat.)±0.01(syst.),B(Ξc0→Σ0K¯∗0)/B(Ξc0→Ξ−π+)=0.69±0.03(stat.)±0.03(syst.),B(Ξc0→Σ+K∗−)/B(Ξc0→Ξ−π+)=0.34±0.06(stat.)±0.02(syst.), where the uncertainties are statistical and systematic, respectively. We obtainB(Ξc0→ΛK¯∗0)=(3.3±0.3(stat.)±0.2(syst.)±1.0(ref.))×10−3,B(Ξc0→Σ0K¯∗0)=(12.4±0.5(stat.)±0.5(syst.)±3.6(ref.))×10−3,B(Ξc0→Σ+K∗0)=(6.1±1.0(stat.)±0.4(syst.)±1.8(ref.))×10−3, where the uncertainties are statistical, systematic, and from B(Ξc0→Ξ−π+), respectively. The asymmetry parameters α(Ξc0→ΛK¯∗0) and α(Ξc0→Σ+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. [Figure not available: see fulltext.]