Weak decays of medium and heavy Λ hypernuclei -: art. no. 044314

We have made a new evaluation of the Lambda decay width in nuclear matter within the propagator method. Through the local density approximation it is possible to obtain results in finite nuclei. We have also studied the dependence of the widths on the NN and Lambda N strong short-range correlations. Using reasonable values for the parameters that control these correlations, as well as realistic nuclear densities and Lambda wave functions, we show that it is possible to reproduce the experimental decay rates in a wide range of mass numbers (from medium to heavy hypernuclei); however, the question related to the Gamma n / Gamma p ratio remains open.