Analysis of the $\eta_1(1855)$ as a $K\bar{K}_1(1400)$ molecular state

TL;DR

This paper investigates whether the $ ext{eta}_1(1855)$ can be understood as a $Kar{K}_1(1400)$ molecular state by analyzing its decay patterns and widths, providing predictions for future experimental verification.

Contribution

It offers a theoretical analysis linking the $ ext{eta}_1(1855)$ to a molecular state hypothesis and predicts decay widths and dominant decay channels for experimental testing.

Findings

Decay width up to 183 MeV consistent with observations

Dominant decay channel is $Kar{K}^* o ext{pi}$

Partial width for $ ext{eta}_1(1855) o ext{gamma} ext{phi}$ up to 17.95 keV

Abstract

In this work, we study the radiative and strong decay of $S$-wave $K\bar{K}_1(1400)$ molecular state within the effective Lagrangians approach and find the relation between the $K\bar{K}_1(1400)$ molecular state and the newly observed $\eta_1(1855)$ state by comparing with the BESIII observation. The prediction indicates that the decay width can reach up to $182.97^{+2.79}_{-3.50}$ MeV, which can be confronted with the experimental data. If the $\eta_1(1855)$ could be $S$-wave $K\bar{K}_1(1400)$ molecular state, the $K\bar{K}^{*}\pi$ three-body decay provides the dominant contribution, not the $\eta\eta^{'}$ channel found in the experiment. In addition, the partial width for $\eta_1(1855)\to\gamma{}\phi$ can reach up to $17.95^{+0.21}_{-0.43}$ KeV. Those results can be measured in future experiments and used to test the nature of the $\eta_1(1855)$.