Impulse Model for the ReactionsK−+He4→Y+π+H3

An impulse model is presented for the reactions $K^{-}+{\mathrm{He}}^4\to Y+\pi +{\mathrm{H}}^3$. The model incorporates the low-energy $\overline{K}$-nucleon parametrization of Kim. The calculation is done for capture at rest from both $s$ and $p$ atomic orbital states and also for kaon interactions in flight. The results are compared with experiment for the final states $\Lambda {\pi }^{-}{\mathrm{He}}^3$ and ${\Sigma }^{+}{\pi }^{-}{\mathrm{H}}^3$ from at-rest kaon interactions.