Measurement of Branching Fractions of ${\Lambda }_c^{+}\to \eta \Lambda {\pi }^{+}$, $\eta {\Sigma }^0{\pi }^{+}$, $\Lambda (1670){\pi }^{+}$, and $\eta \Sigma (1385{)}^{+}$

Abstract

We report branching fraction measurements of four decay modes of the ${\Lambda }_c^{+}$ baryon, each of which includes an $\eta$ meson and a $\Lambda$ baryon in the final state, and all of which are measured relative to the ${\Lambda }_c^{+}\to p{K}^{-}p{i}^{+}$ decay mode. The results are based on a $980\mathrm{f}{\mathrm{b}}^{-1}$ data sample collected by the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider. Two decays, $\eta {\Sigma }^0{\pi }^{+}$ and $\Lambda (1670){\pi }^{+}$, are observed for the first time, while the measurements of the other decay modes, ${\Lambda }_c^{+}\to \eta \Lambda {\pi }^{+}$ and $\eta \Sigma (1385{)}^{+}$, are more precise than those made previously. We obtain $\mathcal{B}({\Lambda }_c^{+}\to \eta \Lambda {\pi }^{+})/\mathcal{B}({\Lambda }_c^{+}\to p{K}^{-}{\pi }^{+})$ = $0.293\pm 0.003\pm 0.014$, $\mathcal{B}({\Lambda }_c^{+}\to \eta {\Sigma }^0{\pi }^{+})/\mathcal{B}({\Lambda }_c^{+}\to p{K}^{-}{\pi }^{+})$ = $0.120\pm 0.006\pm 0.006$, $\mathcal{B}({\Lambda }_c^{+}\to \Lambda (1670){\pi }^{+})\times \mathcal{B}(\Lambda (1670)\to \eta \Lambda )/\mathcal{B}({\Lambda }_c^{+}\to p{K}^{-}{\pi }^{+})$ = $(5.54\pm 0.29\pm 0.73)\times 10^{-2}$, and $\mathcal{B}({\Lambda }_c^{+}\to \eta \Sigma (1385{)}^{+})/\mathcal{B}({\Lambda }_c^{+}\to p{K}^{-}{\pi }^{+})$ = $0.192\pm 0.006\pm 0.016$. The mass and width of the $\Lambda (1670)$ are also precisely determined to be $1674.3\pm 0.8\pm 4.9\mathrm{MeV}/c^2$ and $36.1\pm 2.4\pm 4.8\mathrm{MeV}$, respectively, where the uncertainties are statistical and systematic, respectively.

To be submitted to Physical Review D

References in corpus (1)

• PYTHIA 6.4 Physics and Manual

Cited by in corpus (11)

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• Evidence of the low-lying baryon ${\Sigma }^{\ast }(1/2^{-})$ in the process ${\Lambda }_c^{+}\to \eta {\pi }^{+}\Lambda$
• Roles of $a_0(980)$, $\Lambda (1670)$, and $\Sigma (1385)$ in the ${\Lambda }_c^{+}\to \eta \Lambda {\pi }^{+}$ decay
• Theoretical study of $N(1535)$ and ${\Sigma }^{\ast }(1/2^{-})$ in the Cabibbo-favored process ${\Lambda }_c^{+}\to p{\bar{K}}^0\eta$
• Cabibbo-favored ${\Lambda }_c^{+}\to \Lambda a_0(980{)}^{+}$ decay in the final state interaction
• Nonleptonic three-body charmed baryon weak decays with H(15)
• Observation of ${\Lambda }_c^{+}\to \Lambda a_0(980{)}^{+}$ and Evidence for $\Sigma (1380{)}^{+}$ in ${\Lambda }_c^{+}\to \Lambda {\pi }^{+}\eta$
• Study of the resonance contributions in the ${\Xi }_b^{-}\to p{K}^{-}{K}^{-}$ decay
• The dynamically generated $N(1535)$ state in the ${\Lambda }_c^{+}\to p{\bar{K}}^0{\pi }^0$ decay
• Amplitude analysis and branching fraction measurement of $J/\psi \to \Lambda {\bar{\Sigma }}^0\eta +c.c$
• Probing the isospin structure and low-lying resonances in ${\Lambda }_c^{+}\to n{\bar{K}}^0{\pi }^{+}$ decays