Speaker
Description
The newly reported $\eta_1(1855)$ with $J^{PC}=1^{-+}$ is interpreted to
be a dynamically generated pole in $f_1(1285)\eta-K_{1}(1400)\bar{K}$
scattering with Weinberg-Tomozawa term serves as interaction.
When $a_1-\pi$ mixing in axial meson dominance model is included,
the ratio in $\eta_1(1855)$ decaying into
final states $\eta \eta^{\prime}$ and $K^{\ast}\bar{K}\pi$ is around
$\left(0.54^{-0.20}_{+0.35}\right)^A $ or $\left(0.37^{-0.14}_{+0.33}\right)^B$ in
choices on the mixing angles in $1^+$ mesons.
Furthermore, its $SU(3)$ partners are studied as well,
where $\pi_1(1600)$ may correspond to a pole in $f_1(1420)\pi-K_1(1270)\bar{K}-K_1(1400)\bar{K}$ scattering and
the pole generated in $f_1(1285)K-K_1(1270)\eta$ scattering relates to a sharp jump in $\phi K^+$ invariant mass
distributions in $B^+\to J/\psi \phi K^+$, latter of which can decay into $\eta K$ and be a good way
to test the explanation of hadronic molecule in $1^{-+}$ meson spectrum below $2000 \,\rm{MeV}$.
