Faddeev calculation of a $K^{-}pp$ quasi-bound state

Abstract

We report on the first genuinely three-body $\bar{K}NN-\pi \Sigma N$ coupled-channel Faddeev calculation in search for quasi-bound states in the $K^{-}pp$ system. The main absorptivity in the $K^{-}p$ subsystem is accounted for by fitting to $K^{-}p$ data near threshold. Our calculation yields one such quasi-bound state, with $I=1/2$, $J^{\pi }=0^{-}$, bound in the range $B\sim 55-70$ MeV, with a width of $\Gamma \sim 95-110$ MeV. These results differ substantially from previous estimates, and are at odds with the $K^{-}pp\to \Lambda p$ signal observed by the FINUDA collaboration.

Comments: Minor editorial revision; version accepted for publication in Phys. Rev. Lett