${\Lambda }_c^{+}$ decays at BESIII

Abstract

BESIII has made great progress in taking data which is the largest data samples near the ${\Lambda }_c^{+}{\bar{\Lambda }}_c^{-}$ threshold. We have measured the branching fraction of ${\Lambda }_c^{+}\to n{\pi }^{+}$ to be $(6.6\pm 1.2_{stat.}\pm 0.4_{syst.})\times 10^{-4}$ with the statistical significance of 7.3 $\sigma$ firstly using $3.9{\mathrm{fb}}^{-1}$ $e^{+}{e}^{-}$ collision collected with BESIII detector at six center-of-mass energies between 4.612 and 4.699 GeV. With the result of the branching fraction of ${\Lambda }_c^{+}\to p{\pi }^0$ from Belle, the ratio of the branching fractions between ${\Lambda }_c^{+}\to n{\pi }^{+}$ and ${\Lambda }_c^{+}\to p{\pi }^0$ is measured to be larger than 7.2 at 90% confidence level. The branching fractions of ${\Lambda }_c^{+}\to \Lambda {\pi }^{+}$ and ${\Lambda }_c^{+}\to {\Sigma }^0{\pi }^{+}$ are measured to be $(1.31\pm 0.08_{stat.}\pm 0.05_{syst.})\times 10^{-2}$ and $(1.22\pm 0.08_{stat.}\pm 0.07_{syst.})\times 10^{-2}$, respectively, which are consistent with previous BESIII results. More results of ${\Lambda }_c^{+}$ decays will be published with better precision this year using $6.4{\mathrm{fb}}^{-1}$ $e^{+}{e}^{-}$ collision data samples between 4.600 and 4.946 GeV.

2 pages, 2 figures