First Measurement of the $\Lambda_c^+ \to p \eta'$ decay

TL;DR

This paper reports the first measurement of the branching fraction of the decay mbda_c^+  p ' using data from the Belle detector, observing a significant signal and providing new insights into charm baryon decay modes.

Contribution

It provides the first measurement of the mbda_c^+  p ' decay branching fraction, expanding knowledge of singly Cabibbo-suppressed charm baryon decays.

Findings

First observation of mbda_c^+  p ' decay with 5.4 significance.

Measured relative branching fraction ( p ')/( p K^- ) = (7.54 b1 1.32 b1 0.75) dd.

Calculated absolute branching fraction ( p ') = (4.73 b1 0.82 b1 0.47 b1 0.24) dd},

Abstract

We present the first measurement of the branching fraction of the singly Cabibbo-suppressed (SCS) decay $\Lambda_c^+ \to p \eta'$ with $\eta' \to \eta\pi^+\pi^-$, using a data sample corresponding to an integrated luminosity of 981 $\rm fb^{-1}$, collected by the Belle detector at the KEKB $e^{+}$$e^{-}$ asymmetric-energy collider. A significant $\Lambda_c^+$ signal is observed for the first time with a signal significance of 5.4$\sigma$. The relative branching fraction with respect to the normalization mode $\Lambda_c^+ \to pK^-\pi^+$ is measured to be \begin{equation*} \frac{{\cal B}(\Lambda_c^+ \to p \eta')}{{\cal B}(\Lambda_c^+ \to p K^-\pi^+)} = (7.54 \pm 1.32 \pm 0.75) \times 10^{-3}, \end{equation*} where the uncertainties are statistical and systematic, respectively. Using the world-average value of ${\cal B}(\Lambda_c^+ \to p K^-\pi^+) = (6.28\pm0.32)\times10^{-2}$, we obtain \begin{equation*} {\cal B}(\Lambda_c^+ \to p \eta') = (4.73 \pm 0.82 \pm 0.47 \pm 0.24)\times 10^{-4}, \end{equation*} where the uncertainties are statistical, systematic, and from ${\cal B}(\Lambda_c^+ \to pK^-\pi^+)$, respectively.