What makes the peak structure of the $\mathrm{\Lambda }p$ invariant-mass spectrum in the $K^{-}{}^3\mathrm{H}\mathrm{e}\to \mathrm{\Lambda }pn$ reaction?

Recently a peak structure was observed near the $K^{-}pp$ threshold in the in-flight ${}^3\mathrm{H}\mathrm{e}(K^{-},\mathrm{\Lambda }p)n$ reaction of the E15 experiment at J-PARC, which could be a signal of a $\bar{K}NN$ bound state. In order to investigate what is the origin of this peak, we calculate the cross section of this reaction, in particular based on the scenario that the $\bar{K} N N$boundstateisindeedgeneratedanddecaysinto$\Lambda p$. We find that the numerical result of the $\mathrm{\Lambda }p$ invariant-mass spectrum in the $\bar{K} N N$ bound scenario is consistent with the J-PARC E15 data.