Current nuclear physics issues in studying the neutrinoless (μ −, e −) conversion in nuclei

Abstract

The open nuclear physics problems in investigating the exotic μ − e conversion process are reviewed and discussed. A formulation of the nuclear matrix elements, in a compact way for all basic μ − → e − operators originating from a general (nucleon-level) effective Lagrangian, is also presented. The consideration of the nuclear deformation, which had not been taken into account in previous calculations performed with normal QRPA, is examined. As an example the low-lying spectrum of 72 Ge isotope, which has been chosen for future calculation in the context of the deformed Hartree-Fock method, is preliminary discussed.