Amplitude analysis of the charmed baryon decay Lambda_c+ to p K_S^0 pi0

Abstract

Using $e^{+}{e}^{-}$ annihilation data corresponding to an integrated luminosity of 4.5 fb${}^{-1}$ collected with the BESIII detector at center-of-mass energies between 4.600 and 4.699 GeV, the first amplitude analysis of the charmed baryon decay ${\Lambda }_c^{+}\to p{K}_S^0{\pi }^0$ is performed. The processes ${\Lambda }_c^{+}\to p{\bar{K}}^{\ast }(892{)}^0$, ${\Lambda }_c^{+}\to \Delta (1600{)}^{+}{K}_S^0$, and ${\Lambda }_c^{+}\to N(1710{)}^{+}{K}_S^0$ are identified with statistical significances of $12.8\sigma$, $14.5\sigma$, and $6.2\sigma$, respectively. The mass and width of $\Delta (1600{)}^{+}$ are measured to be $(1520.4\pm 8.8\pm 37.7)\text{MeV}$ and $(199.4\pm 26.4\pm 39.9)\text{MeV}$, respectively. The mass and width of $N(1710{)}^{+}$ are measured to be $(1719.7\pm 9.4\pm 9.1)\text{MeV}$ and $(72.0\pm 18.0\pm 15.0)\text{MeV}$, respectively. The branching fractions of these processes are determined to be $\mathcal{B}[{\Lambda }_c^{+}\to \Delta (1600{)}^{+}(\to p{\pi }^0)K_S^0]=(8.10\pm 0.80\pm 5.57)\times 10^{-3}$, $\mathcal{B}[{\Lambda }_c^{+}\to N(1710{)}^{+}(\to p{\pi }^0)K_S^0]=(1.58\pm 0.48\pm 0.77)\times 10^{-3}$, and $\mathcal{B}[{\Lambda }_c^{+}\to p{\bar{K}}^{\ast }(892{)}^0(\to K_S^0{\pi }^0)]=(2.63\pm 0.47\pm 0.29)\times 10^{-3}$, where the first uncertainties are statistical and the second systematic.