Higher order terms of the nucleon current in the neutrino mass mechanism of neutrinoless double beta decay

The nuclear matrix elements for light and heavy Majorana neutrino in neutri noless double beta decay have been reconsidered by including additional hig her order terms in the nucleon current. The form of the nucleon current now includes except the usual vector and axial-vector terms additional contrib utions arising from weak magnetism and induced pseudoscalar coupling. The l ater is derived by the partially conserved axial-Vector current hypothesis. We have considered all nuclei that undergo double beta decay in the mass r egion A=76 up to A=150 using the renormalized quasiparticle random phase ap proximation. Our results show that these contributions are very important. They bring significant reductions to the nuclear matrix element for both th e light and the heavy neutrino. Thus new limits for the neutrino mass are e xtracted using the best presently available experimental limits on the half -life of neutrinoless double beta-decay.