Λ hypernuclear production in (Kstop-,π) reactions reexamined

Distorted-wave impulse approximation calculations of Λ hypernuclear production rates in stopped K^- reactions on several p-shell targets used recently in experiments by the FINUDA Collaboration are reported. Chirally motivated K^-N→πΛ in-medium transition amplitudes are employed, and the sensitivity of the calculated rates to the initial K ^--atomic wave functions and final pion distorted waves is studied. The calculated rates are compared with measured rates, wherever available, which confirm earlier observations that (i) the calculated rates are generally lower than the measured rates, and (ii) the deeper the K^--nuclear potential, the worse the discrepancy. The A dependence of the calculated 1sΛ production rates is discussed, providing a useful tool to resolve the issue of depth of the K^--nuclear potential near threshold.