Eur. Phys. J. C (2024) 84: 52
https://doi.org/10.1140/epjc/s10052-024-12405-5

Regular Article - Theoretical Physics

$\mathit{J}\mathbf{/}\mathit{\psi }$ decays into $\omega (\varphi )f_1(1285)$ and $\omega (\varphi )``f_1(1420)$”

¹ Department of Physics, Guangxi Normal University, 541004, Guilin, China
² School of Physics, Southeast University, 210094, Nanjing, China
³ Guangxi Key Laboratory of Nuclear Physics and Technology, Guangxi Normal University, 541004, Guilin, China
⁴ Departamento de Física Teórica and IFIC, Centro Mixto Universidad de Valencia-CSIC Institutos de Investigación de Paterna, Aptdo. 22085, 46071, Valencia, Spain

^c liangwh@gxnu.edu.cn

Received: 17 November 2023
Accepted: 5 January 2024
Published online: 18 January 2024

Abstract

We perform a theoretical study of the $J/\psi \to \omega (\varphi )K^{\ast }\overline{K}+c.c.\to \omega (\varphi )K^0{\pi }^{+}{K}^{-}$ reactions with the assumption that the $f_1(1285)$ is dynamically generated from a single channel $K^{\ast }\overline{K}+c.c$ interaction in the chiral unitary approach. Two peaks in the $K^0{\pi }^{+}{K}^{-}$ invariant mass distribution are observed, one clear peak locates at the $f_1(1285)$ nominal mass, the other peak locates at around $1420\text{MeV}$ with about $70\text{MeV}$ width. We conclude that the former peak is associated with the $f_1(1285)$ and the latter peak is not a genuine resonance but a manifestation of the kinematic effect in the higher energy region caused by the $K^{\ast }\overline{K}+c.c.$ decay mode of the $f_1(1285)$.