Pionic decay of Lambda Hypernuclei in a Continuum Shell Model

Abstract

We evaluate pionic decay widths of Lambda hypernuclei using a shell model for, both the nuclear bound and the continuum nucleon wave functions in the final state, and distorted waves for the outgoing pion. An excellent agreement with the recent KEK measurement of ${\pi }^{-}$-decay widths of ${}_{\Lambda }^{12}$C and ${}_{\Lambda }^{28}$Si is found. Besides, results for ${}_{\Lambda }^{56}$Fe are consistent with the existing upper bound.

Comments: 19 pages, 4 figures, 7 tables, revised version to be published in Phys. Rev. C