# Evidence for the singly-Cabibbo-suppressed decay $\Lambda_{c}^{+} \to p\eta$ and search for $\Lambda_{c}^{+} \to p\pi^{0}$

## TL;DR

This paper reports the first evidence for the decay mbda_c^+ ta and sets an upper limit for mbda_c^+ pi^0, advancing understanding of charmed baryon decay modes.

## Contribution

It provides the first experimental evidence for mbda_c^+ ta decay and measures its branching fraction, while also setting an upper limit for mbda_c^+ pi^0 decay.

## Key findings

- First evidence for mbda_c^+ ta decay with 4.2 significance.
- Measured branching fraction mbda_c^+ ta: (1.24 b1 0.28 b1 0.10) d7 10^{-3}.
- Upper limit for mbda_c^+ pi^0: < 2.7 d7 10^{-4} at 90% CL.

## Abstract

We study the singly-Cabibbo-suppressed decays $\Lambda_c^{+}\to p\eta$ and $\Lambda_{c}^{+}\to p\pi^{0}$ using $\Lambda_{c}^{+}\Lambda_{c}^{+}$ pairs produced by $e^+e^-$ collisions at a center-of-mass energy of $\sqrt{s} = 4.6\; GeV$. The data sample was collected by the BESIII detector at the BEPCII collider and corresponds to an integrated luminosity of 567 $pb^{-1}$. We find the first evidence for the decay $\Lambda_{c}^{+}\to p \eta$ with a statistical significance of $4.2\sigma$ and measure its branching fraction to be $\mathcal{B}(\Lambda_c^+\to p\eta)= (1.24\pm0.28({\rm{stat.}})\pm0.10({\rm{syst.}}))\times10^{-3}$. No significant $\Lambda_c^+ \to p\pi^0$ signal is observed. We set an upper limit on its branching fraction $\mathcal{B}(\Lambda_c^+ \to p\pi^{0}) < 2.7 \times 10^{-4}$ at the 90% confidence level.