The $Λ_c^+\toΛπ^+π^+π^-$ reaction, and a triangle singularity producing the $Σ^*(1430)$ state

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Li, Yi-Yao, Song, Jing, Oset, Eulogio, Liang, Wei-Hong, Molina, Raquel
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913863329382400
author Li, Yi-Yao
Song, Jing
Oset, Eulogio
Liang, Wei-Hong
Molina, Raquel
author_facet Li, Yi-Yao
Song, Jing
Oset, Eulogio
Liang, Wei-Hong
Molina, Raquel
contents We study the decay $Λ_c^+ \to Λπ^+ π^+ π^-$, focusing on the production of the $Σ^*(1430)$ resonance observed by the Belle Collaboration. Interpreted as a dynamically generated state from meson-baryon interactions in the chiral unitary approach, the $Σ^*(1430)$ signal is shown to be enhanced by a triangle singularity involving intermediate $K^{*-}$, $p$, and $\bar K^0$ states. This mechanism leads to a sharp peak near 1434 MeV in the $π^+ Λ$ invariant mass distribution, in agreement with the experimental observations, and predicts a secondary peak around 1875 MeV in the $π^- Σ^*(1430)$ spectrum tied to the triangle singularity. We also estimate the branching ratio of $Λ_c^+ \to π^+ π^- Σ^*(1430)$ to be about $3.5 \times 10^{-4}$. The results for the branching ratio and the $π^- Σ^*(1430)$ mass distributions are predictions of the theoretical approach, which could be tested with reanalysis of existing data.
format Preprint
id arxiv_https___arxiv_org_abs_2505_21403
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle The $Λ_c^+\toΛπ^+π^+π^-$ reaction, and a triangle singularity producing the $Σ^*(1430)$ state
Li, Yi-Yao
Song, Jing
Oset, Eulogio
Liang, Wei-Hong
Molina, Raquel
High Energy Physics - Phenomenology
We study the decay $Λ_c^+ \to Λπ^+ π^+ π^-$, focusing on the production of the $Σ^*(1430)$ resonance observed by the Belle Collaboration. Interpreted as a dynamically generated state from meson-baryon interactions in the chiral unitary approach, the $Σ^*(1430)$ signal is shown to be enhanced by a triangle singularity involving intermediate $K^{*-}$, $p$, and $\bar K^0$ states. This mechanism leads to a sharp peak near 1434 MeV in the $π^+ Λ$ invariant mass distribution, in agreement with the experimental observations, and predicts a secondary peak around 1875 MeV in the $π^- Σ^*(1430)$ spectrum tied to the triangle singularity. We also estimate the branching ratio of $Λ_c^+ \to π^+ π^- Σ^*(1430)$ to be about $3.5 \times 10^{-4}$. The results for the branching ratio and the $π^- Σ^*(1430)$ mass distributions are predictions of the theoretical approach, which could be tested with reanalysis of existing data.
title The $Λ_c^+\toΛπ^+π^+π^-$ reaction, and a triangle singularity producing the $Σ^*(1430)$ state
topic High Energy Physics - Phenomenology
url https://arxiv.org/abs/2505.21403