Phys Rev Lett. 2023 Jan 20;130(3):031901. doi: 10.1103/PhysRevLett.130.031901.
We present the study of B[over ¯]^{0}→Σ_{c}(2455)^{0,++}π^{±}p[over ¯] decays based on 772×10^{6} BB[over ¯] events collected with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The Σ_{c}(2455)^{0,++} candidates are reconstructed via their decay to Λ_{c}^{+}π^{∓} and Λ_{c}^{+} decays to pK^{-}π^{+}, pK_{S}^{0}, and Λπ^{+} final states. The corresponding branching fractions are measured to be B(B[over ¯]^{0}→Σ_{c}(2455)^{0}π^{+}p[over ¯])=(1.09±0.06±0.07)×10^{-4} and B(B[over ¯]^{0}→Σ_{c}(2455)^{++}π^{-}p[over ¯])=(1.84±0.11±0.12)×10^{-4}, which are consistent with the world average values with improved precision. A new structure is found in the M_{Σ_{c}(2455)^{0,++}π^{±}} spectrum with a significance of 4.2σ including systematic uncertainty. The structure is possibly an excited Λ_{c}^{+} and is tentatively named Λ_{c}(2910)^{+}. Its mass and width are measured to be (2913.8±5.6±3.8) MeV/c^{2} and (51.8±20.0±18.8) MeV, respectively. The products of branching fractions for the Λ_{c}(2910)^{+} are measured to be B(B[over ¯]^{0}→Λ_{c}(2910)^{+}p[over ¯])×B(Λ_{c}(2910)^{+}→Σ_{c}(2455)^{0}π^{+})=(9.5±3.6±1.6)×10^{-6} and B(B[over ¯]^{0}→Λ_{c}(2910)^{+}p[over ¯])×B(Λ_{c}(2910)^{+}→Σ_{c}(2455)^{++}π^{-})=(1.24±0.35±0.10)×10^{-5}. Here, the first and second uncertainties are statistical and systematic, respectively.
我们展示了基于 Belle 探测器在 KEKB 不对称能电子-正电子对撞机上收集的 772×10^{6} BB[over ¯]事件对 B[over ¯]^{0}→Σ_{c}(2455)^{0,++}π^{±}p[over ¯]衰变的研究。Σ_{c}(2455)^{0,++}候选物通过它们的 Λ_{c}^{+}π^{∓}衰变和 Λ_{c}^{+}衰变到 pK^{-}π^{+}、pK_{S}^{0}和 Λπ^{+}终态来重建。测量到相应的分支比为 B(B[over ¯]^{0}→Σ_{c}(2455)^{0}π^{+}p[over ¯])=(1.09±0.06±0.07)×10^{-4}和 B(B[over ¯]^{0}→Σ_{c}(2455)^{++}π^{-}p[over ¯])=(1.84±0.11±0.12)×10^{-4}，这与世界平均值一致，精度有所提高。在 M_{Σ_{c}(2455)^{0,++}π^{±}}谱中发现了一个新结构，其显著性为 4.2σ，包括系统不确定性。该结构可能是一个激发的 Λ_{c}^{+}，并被暂时命名为 Λ_{c}(2910)^{+}。测量到它的质量和宽度分别为(2913.8±5.6±3.8) MeV/c^{2}和(51.8±20.0±18.8) MeV。 Λ_{c}(2910)^{+}的分支比产物测量值为 B(B[over ¯]^{0}→Λ_{c}(2910)^{+}p[over ¯])×B(Λ_{c}(2910)^{+}→Σ_{c}(2455)^{0}π^{+})=(9.5±3.6±1.6)×10^{-6}和 B(B[over ¯]^{0}→Λ_{c}(2910)^{+}p[over ¯])×B(Λ_{c}(2910)^{+}→Σ_{c}(2455)^{++}π^{-})=(1.24±0.35±0.10)×10^{-5}。这里，第一个和第二个不确定性分别是统计和系统的。
