  In this paper a microscopic state-of-the-art approach to calculation of the
nuclear matrix element $M^{0\nu}$ for neutrinoless double beta decay with an
account for nuclear deformation is presented in length and applied for
$^{76}$Ge, $^{150}$Nd and $^{160}$Gd. The proton-neutron quasiparticle random
phase approximation (QRPA) with a realistic residual interaction [the Brueckner
$G$ matrix derived from the charge-depending Bonn (Bonn-CD) nucleon-nucleon
potential] is used as the underlying nuclear structure model. The effects of
the short range correlations and the quenching of the axial vector coupling
constant $g_A$ are analyzed. The results show that neutrinoless double beta
decay of $^{150}$Nd, to be measured soon by the SNO+ collaboration, provides
one of the best probes of the Majorana neutrino mass. This confirms our
preliminary conclusion in Ref. {Fang10}.

Nuclear Theory