Cetin, Serkant AliKolcu, Onur Buğra2022-05-232022-05-232022Ablikim M, Achasov M. N, Begzsuren K, Berger N, Bertani M, Bettoni D, Cetin, S. A, Chen Z. J, Cheng W. S, Cibinetto G, Cossio F, Cui X. F, Guo A. Q, Guo L. B, Guo R. P, Guo Y. P, Guskov A, Jing M. Q, Johansson T, Kalantar-Nayestanaki N, Kolcu, O. B T, Li C, Li C. H, Li C, Li D. M, Li F, Li G, Liu W. M, Liu X, Liu Y, Liu Y. B, Liu Z. A, Liu ZQ, Lou X. C, BESIII Collaboration. Observation of the Singly Cabibbo Suppressed Decay Λ_{c}^{+}→nπ^{+}. Phys Rev Lett. 2022 Apr 8;128(14):142001. doi: 10.1103/PhysRevLett.128.142001. PMID: 35476477.0031-9007http://doi.org/110.1103/PhysRevLett.128.142001https://hdl.handle.net/20.500.12713/2696The singly Cabibbo-suppressed decay ?_{c}^{+}?n?^{+} is observed for the first time with a statistical significance of 7.3? by using 3.9 fb^{-1} of e^{+}e^{-} collision data collected at center-of-mass energies between 4.612 and 4.699 GeV with the BESIII detector at BEPCII. The branching fraction of ?_{c}^{+}?n?^{+} is measured to be (6.6±1.2_{stat}±0.4_{syst})×10^{-4}. By taking the upper limit of branching fractions of ?_{c}^{+}?p?^{0} from the Belle experiment, the ratio of branching fractions between ?_{c}^{+}?n?^{+} and ?_{c}^{+}?p?^{0} is calculated to be larger than 7.2 at the 90% confidence level, which disagrees with most predictions of the available phenomenological models. In addition, the branching fractions of the Cabibbo-favored decays ?_{c}^{+}???^{+} and ?_{c}^{+}??^{0}?^{+} are measured to be (1.31±0.08_{stat}±0.05_{syst})×10^{-2} and (1.22±0.08_{stat}±0.07_{syst})×10^{-2}, respectively, which are consistent with previous results.eninfo:eu-repo/semantics/closedAccessArticle1281435476477WOS:0007890183000012-s2.0-85128907360Q110.1103/PhysRevLett.128.142001Q1