Amplitude analysis of the KS0KS0 system produced in the reaction π−p→KS0KS0n at 23 GeV/c

Abstract

We have carried out an amplitude analysis of the $K_S^0{K}_S^0$ system produced in the reaction ${\pi }^{-}p\to K_S^0{K}_S^{0}n$ at 23 GeV/c, based on about 15 000 events in the low-$t$ region ($|t-t_{min}|<\mathrm{}0.1\mathrm{}$ Ge${\mathrm{V}}^2$). Below 1.6 GeV/${\mathit{c}}^2$, our favored solution is very similar to those from previous analyses. For higher masses, we observe the $K_S^0{K}_S^0$ decay of the $h\left(2040\right)\mathrm{}$ meson. In addition, the $l=0\mathrm{}$ partial wave contains a new state, strongly coupled to $K_S^0{K}_S^0$, with parameters $M={1.771}_{-0.053\mathrm{}}^{+0.077\mathrm{}}$ GeV/${\mathit{c}}^2$ and $\Gamma ={0.200}_{-0.009\mathrm{}}^{+0.156\mathrm{}}$ GeV/${\mathit{c}}^2$. Since this state is most probably $I=0\mathrm{}$, we call it the $S^{*\prime }\mathrm{}\left(1770\right)\mathrm{}$. We find an $\frac{f^{\prime }}{f}$ production ratio of ${0.23}_{-0.13\mathrm{}}^{+0.14\mathrm{}}$, and branching ratios for $f$-meson and $h\left(2040\right)\mathrm{}$-meson decays into $K\overline{K}$ of (${3.1}_{-1.7\mathrm{}}^{+0.7\mathrm{}}$)% and (${0.67}_{-0.15\mathrm{}}^{+0.41\mathrm{}}$)%, respectively. We find, in a detailed comparison of our results with those from other experiments, that our solution is compatible with all known features of both charged and neutral $K\overline{K}$ systems.