Testing the origin of the "$f_1(1420)$" with the $\bar{K}p\to \Lambda (\Sigma )K\bar{K}\pi$ reaction

Abstract

We study the $\bar{K}p\to YK\bar{K}\pi$ reactions with $\bar{K}={\bar{K}}^0,K^{-}$ and $Y={\Sigma }^0,{\Sigma }^{+},\Lambda$, in the region of $K\bar{K}\pi$ invariant masses of $1200-1550$ MeV. The strong coupling of the $f_1(1285)$ resonance to $K^{\ast }\bar{K}$ makes the mechanism based on $K^{\ast }$ exchange very efficient to produce this resonance observed in the $K\bar{K}\pi$ invariant mass distribution. In addition, in all the reactions one observes an associated peak at $1420$ MeV which comes from the $K^{\ast }\bar{K}$ decay mode of the $f_1(1285)$ when the $K^{\ast }$ is placed off shell at higher invariant masses. We claim this to be the reason for the peak of the $K^{\ast }\bar{K}$ distribution seen in the experiments which has been associated to the "$f_1(1420)$" resonance.

Comments: 11 pages, 4 figures