Saved in:
Bibliographic Details
Main Author: Nam, Seung-il
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2603.21041
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915880803237888
author Nam, Seung-il
author_facet Nam, Seung-il
contents We study the thermal modification of the exclusive decay $K_1^+(1270)\to π^+π^-K^+$ in a hot hadronic medium. The decay amplitude is constructed from effective hadronic interactions dominated by the $ρ$- and $K^*$-pole contributions, which enables a Dalitz-level analysis of the three-body decay in medium. Thermal effects associated with partial chiral-symmetry restoration are incorporated through a phenomenological interpolation toward vector--axial-vector degeneracy near the chiral crossover. As the temperature increases, the reduction of the parent $K_1$ mass strongly compresses the available three-body phase space, leading to substantial deformation of the Dalitz distribution and invariant-mass spectra, as well as to a pronounced suppression of $Γ_{K_1\toπ^+π^-K^+}(T)$. As a further step toward future experimental comparison, we introduce normalized shape observables that quantify the thermal evolution of the $K^*$-dominated $πK$ region, the upper-edge weight of the $ππ$ spectrum, and the compactification of the Dalitz population. The dominant effect identified in the present framework is therefore kinematic: thermal phase-space reduction in the strange axial-vector channel. These results suggest that the exclusive $K_1(1270)$ channel may provide a useful qualitative probe of in-medium strange axial-vector dynamics near the pseudocritical region.
format Preprint
id arxiv_https___arxiv_org_abs_2603_21041
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Thermal modification of $K_1(1270)\to π^+π^-K^+$ in a hot hadronic medium
Nam, Seung-il
High Energy Physics - Phenomenology
We study the thermal modification of the exclusive decay $K_1^+(1270)\to π^+π^-K^+$ in a hot hadronic medium. The decay amplitude is constructed from effective hadronic interactions dominated by the $ρ$- and $K^*$-pole contributions, which enables a Dalitz-level analysis of the three-body decay in medium. Thermal effects associated with partial chiral-symmetry restoration are incorporated through a phenomenological interpolation toward vector--axial-vector degeneracy near the chiral crossover. As the temperature increases, the reduction of the parent $K_1$ mass strongly compresses the available three-body phase space, leading to substantial deformation of the Dalitz distribution and invariant-mass spectra, as well as to a pronounced suppression of $Γ_{K_1\toπ^+π^-K^+}(T)$. As a further step toward future experimental comparison, we introduce normalized shape observables that quantify the thermal evolution of the $K^*$-dominated $πK$ region, the upper-edge weight of the $ππ$ spectrum, and the compactification of the Dalitz population. The dominant effect identified in the present framework is therefore kinematic: thermal phase-space reduction in the strange axial-vector channel. These results suggest that the exclusive $K_1(1270)$ channel may provide a useful qualitative probe of in-medium strange axial-vector dynamics near the pseudocritical region.
title Thermal modification of $K_1(1270)\to π^+π^-K^+$ in a hot hadronic medium
topic High Energy Physics - Phenomenology
url https://arxiv.org/abs/2603.21041