Two dynamical generated $a_0$ resonances by interactions between vector mesons

Abstract

We study dynamically generated $a_0$ resonances by interactions between vector mesons including their coupling to channels of pseudoscalar mesons within coupled-channel approach. Both vector and pseudoscalar mesons are considered as $t$-channel exchanged mesons for calculating interactions between vector mesons. Analogous to $a_0(980)$ as a $K\bar{K}-\pi \eta$ dynamically generated state, there is an $a_0(1710)$ as a coupled channel dynamically generated state near $K^{\ast }{\bar{K}}^{\ast }$ threshold. The channels involved are $\rho \varphi ,K^{\ast }{\bar{K}}^{\ast },\rho \omega ,K\bar{K},\pi \eta$. This $a_0$ mainly decays to $\rho \omega$, $\pi \eta$ and $K\bar{K}$. This pole is much tied to the coupled channel effect. If we turn off either $\rho \varphi$ or $K^{\ast }{\bar{K}}^{\ast }$, the pole disappears. In addition, it is found that $a_0(1450)$ may also be dynamically generated by $\rho \omega$ interactions due to $\pi$ and $\eta$ exchange.

Comments: arXiv admin note: substantial text overlap with arXiv:2107.14470