Based on a sample of \left(10087\pm 44\right)\times {10}^{6}J/\psi events collected with the BESIII detector, a partial-wave analysis of J/\psi \rightarrow \Lambda {\bar{\Sigma }}^{0}\eta +\mathrm{c}.\mathrm{c}.is performed for the first time. The dominant contributions are found to arise from excited Λstates with J^{P}={\frac{1}{2}}^{-}and J^{P}={\frac{1}{2}}^{+}in the ηΛinvariant mass spectrum. The measured masses and widths are M=\left(1668.8\pm 3.1\pm 21.2\right)\text{\ }\mathrm{MeV}/c^{2},\ \Gamma =\left(52.7\pm 4.2\pm 17.8\right)\text{\ }\mathrm{MeV} for the \Lambda \left(1670\right), and M=\left(1881.5\pm 16.5\pm 20.3\right)\text{\ }\mathrm{MeV}/c^{2},\ \Gamma =\left(82.4\pm 18.2\pm 8.9\right)\text{\ }\mathrm{MeV} for the \Lambda \left(1810\right), respectively. The branching fraction is determined to be \mathcal{B}\left(J/\psi \rightarrow \Lambda {\bar{\Sigma }}^{0}\eta +\mathrm{c}.\mathrm{c}.\right)=\left(3.44\pm 0.11\pm 0.13\right)\times {10}^{-5}, where the first uncertainties are statistical and the second are systematic.
Amplitude analysis and branching fraction measurement of J/ψ → ΛΣ¯ 0η + c.c.
Garzia, I.;Melendi, F. M.;
2026
Abstract
Based on a sample of \left(10087\pm 44\right)\times {10}^{6}J/\psi events collected with the BESIII detector, a partial-wave analysis of J/\psi \rightarrow \Lambda {\bar{\Sigma }}^{0}\eta +\mathrm{c}.\mathrm{c}.is performed for the first time. The dominant contributions are found to arise from excited Λstates with J^{P}={\frac{1}{2}}^{-}and J^{P}={\frac{1}{2}}^{+}in the ηΛinvariant mass spectrum. The measured masses and widths are M=\left(1668.8\pm 3.1\pm 21.2\right)\text{\ }\mathrm{MeV}/c^{2},\ \Gamma =\left(52.7\pm 4.2\pm 17.8\right)\text{\ }\mathrm{MeV} for the \Lambda \left(1670\right), and M=\left(1881.5\pm 16.5\pm 20.3\right)\text{\ }\mathrm{MeV}/c^{2},\ \Gamma =\left(82.4\pm 18.2\pm 8.9\right)\text{\ }\mathrm{MeV} for the \Lambda \left(1810\right), respectively. The branching fraction is determined to be \mathcal{B}\left(J/\psi \rightarrow \Lambda {\bar{\Sigma }}^{0}\eta +\mathrm{c}.\mathrm{c}.\right)=\left(3.44\pm 0.11\pm 0.13\right)\times {10}^{-5}, where the first uncertainties are statistical and the second are systematic.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
