Measurements of branching fractions and asymmetry parameters of Ξ c 0 → Λ K ¯ ∗ 0 $$ {\Xi}_c^0\to \Lambda {\overline{K}}^{\ast 0} $$ , Ξ c 0 → Σ 0 K ¯ ∗ 0 $$ {\Xi}_c^0\to {\Sigma}^0{\overline{K}}^{\ast 0} $$ , and Ξ c 0 → Σ + K ∗ − $$ {\Xi}_c^0\to {\Sigma}^{+}{K}^{\ast -} $$ decays at Belle

Abstract

Abstract 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 Ξ c 0 → Λ K ¯ ∗ 0 $$ {\Xi}_c^0\to \Lambda {\overline{K}}^{\ast 0} $$ , Ξ c 0 → Σ 0 K ¯ ∗ 0 $$ {\Xi}_c^0\to {\Sigma}^0{\overline{K}}^{\ast 0} $$ , and Ξ c 0 → Σ + K ∗ − $$ {\Xi}_c^0\to {\Sigma}^{+}{K}^{\ast -} $$ for the first time. The relative branching ratios to the normalization mode of Ξ c 0 → Ξ − π + $$ {\Xi}_c^0\to {\Xi}^{-}{\pi}^{+} $$ are measured to be B Ξ c 0 → Λ K ¯ ∗ 0 / B Ξ c 0 → Ξ − π + = 0.18 ± 0.02 stat . ± 0.01 syst . , B Ξ c 0 → Σ 0 K ¯ ∗ 0 / B Ξ c 0 → Ξ − π + = 0.69 ± 0.03 stat . ± 0.03 syst . , B Ξ c 0 → Σ + K ∗ − / B Ξ c 0 → Ξ − π + = 0.34 ± 0.06 stat . ± 0.02 syst . , $$ {\displaystyle \begin{array}{c}\mathcal{B}\left({\Xi}_c^0\to \Lambda {\overline{K}}^{\ast 0}\right)/\mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right)=0.18\pm 0.02\left(\mathrm{stat}.\right)\pm 0.01\left(\mathrm{syst}.\right),\\ {}\mathcal{B}\left({\Xi}_c^0\to {\Sigma}^0{\overline{K}}^{\ast 0}\right)/\mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right)=0.69\pm 0.03\left(\mathrm{stat}.\right)\pm 0.03\left(\mathrm{syst}.\right),\\ {}\mathcal{B}\left({\Xi}_c^0\to {\Sigma}^{+}{K}^{\ast -}\right)/\mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right)=0.34\pm 0.06\left(\mathrm{stat}.\right)\pm 0.02\left(\mathrm{syst}.\right),\end{array}} $$ where the uncertainties are statistical and systematic, respectively. We obtain B Ξ c 0 → Λ K ¯ ∗ 0 = 3.3 ± 0.3 stat . ± 0.2 syst . ± 1.0 ref . × 10 − 3 , B Ξ c 0 → Σ 0 K ¯ ∗ 0 = 12.4 ± 0.5 stat . ± 0.5 syst . ± 3.6 ref . × 10 − 3 , B Ξ c 0 → Σ + K ∗ 0 = 6.1 ± 1.0 stat . ± 0.4 syst . ± 1.8 ref . × 10 − 3 , $$ {\displaystyle \begin{array}{c}\mathcal{B}\left({\Xi}_c^0\to \Lambda {\overline{K}}^{\ast 0}\right)=\left(3.3\pm 0.3\left(\mathrm{stat}.\right)\pm 0.2\left(\mathrm{syst}.\right)\pm 1.0\left(\mathrm{ref}.\right)\right)\times {10}^{-3},\\ {}\mathcal{B}\left({\Xi}_c^0\to {\Sigma}^0{\overline{K}}^{\ast 0}\right)=\left(12.4\pm 0.5\left(\mathrm{stat}.\right)\pm 0.5\left(\mathrm{syst}.\right)\pm 3.6\left(\mathrm{ref}.\right)\right)\times {10}^{-3},\\ {}\mathcal{B}\left({\Xi}_c^0\to {\Sigma}^{+}{K}^{\ast 0}\right)=\left(6.1\pm 1.0\left(\mathrm{stat}.\right)\pm 0.4\left(\mathrm{syst}.\right)\pm 1.8\left(\mathrm{ref}.\right)\right)\times {10}^{-3},\end{array}} $$ where the uncertainties are statistical, systematic, and from B Ξ c 0 → Ξ − π + $$ \mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right) $$ , respectively. The asymmetry parameters α Ξ c 0 → Λ K ¯ ∗ 0 $$ \alpha \left({\Xi}_c^0\to \Lambda {\overline{K}}^{\ast 0}\right) $$ and α Ξ c 0 → Σ + K ∗ − $$ \alpha \left({\Xi}_c^0\to {\Sigma}^{+}{K}^{\ast -}\right) $$ 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.

Keywords

• Branching fraction
• e +-e − Experiments
• Charm physics