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Finite-temperature effects on the threshold cusps in $π π$ and $D {\bar{D}}^{*}$ scatterings from relativistic heavy-ion collisions

Ying Zhang ^1,2,3,4,*, Atsushi Hosaka ^2,5,†, Qian Wang ^1,2,3,6,‡, and Shigehiro Yasui ^7,8,9,§

¹State Key Laboratory of Nuclear Physics and Technology, Institute of Quantum Matter, South China Normal University, Guangzhou 510006, China
²Research Center for Nuclear Physics (RCNP), Osaka University, Ibaraki 567-0047, Japan
³Key Laboratory of Atomic and Subatomic Structure and Quantum Control (MOE), Guangdong-Hong Kong Joint Laboratory of Quantum Matter, Guangzhou 510006, China
⁴Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter, Guangdong Provincial Key Laboratory of Nuclear Science, Guangzhou 510006, China
⁵Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), Tokai 319-1195, Japan
⁶Southern Center for Nuclear-Science Theory (SCNT), Institute of Modern Physics, Chinese Academy of Sciences, Huizhou 516000, Guangdong Province, China
⁷Nishogakusha University, 6-16, Sanbancho, Chiyoda, Tokyo 102-8336, Japan
⁸Research and Education Center for Natural Sciences, Keio University, Hiyoshi 4-1-1, Yokohama, Kanagawa 223-8521, Japan
⁹International Institute for Sustainability with Knotted Chiral Meta Matter (SKCM²), Hiroshima University, 1-3-2 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8511, Japan

^*Contact author: yingzhang@m.scnu.edu.cn, ying@rcnp.osaka-u.ac.jp
^†Contact author: hosaka@rcnp.osaka-u.ac.jp
^‡Contact author: qianwang@m.scnu.edu.cn
^§Contact author: yasuis@keio.jp

Phys. Rev. C 114, 015201 – Published 6 July, 2026

DOI: https://doi.org/10.1103/qxzl-rzz1

Abstract

We investigate how the temperature influences the threshold cusps in meson-meson scatterings, i.e., $π π$ and $D {\bar{D}}^{*}$ (or $D^{*} \bar{D}$ ) scatterings, using the production rates and propagators obtained at finite temperature. The line shape of production rate of $π π$ at different temperatures demonstrates that the cusp structure in $π π$ scattering is mildly enhanced as the temperature increases. For the $π π$ propagator, which includes isospin symmetry breaking, the line shape displays a unique plateaulike structure, and this structure will also be enhanced as the temperature increases. For comparison, the line shape of the $D {\bar{D}}^{*}$ propagator including isospin symmetry breaking is also investigated at different temperatures. As the temperature increases, its line shape shows a similar plateaulike structure but with some different properties when the temperature modifications to the masses and widths of $D$ and ${\bar{D}}^{*}$ are considered.

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Phys. Rev. C 114, 015201– Published 6 July, 2026

Vol. 114, Iss. 1 — July 2026

Received 8 April 2025
Revised 24 April 2026
Accepted 9 June 2026

DOI: https://doi.org/10.1103/qxzl-rzz1

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP³.

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Finite-temperature effects on the threshold cusps in $π π$ and $D {\bar{D}}^{*}$ scatterings from relativistic heavy-ion collisions

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Finite-temperature effects on the threshold cusps in ππ and DD¯* scatterings from relativistic heavy-ion collisions

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References (39)

Finite-temperature effects on the threshold cusps in $π π$ and $D {\bar{D}}^{*}$ scatterings from relativistic heavy-ion collisions