We have examined the importance of momentum dependent induced nucleoncurrents such as weak-magnetism and pseudoscalar couplings to the amplitude ofneutrinoless double beta decay in the mechanisms of light and heavy Majorananeutrino as well as in that of Majoron emission. Such effects are expected tooccur in all nuclear models in the direction of reducing the light neutrinomatrix elements by about 30%. To test this we have performed a calculation ofthe nuclear matrix elements of the experimentally interesting nuclei A = 76,82, 96, 100, 116, 128, 130, 136 and 150 within the pn-RQRPA. We have found thatindeed such corrections vary somewhat from nucleus to nucleus, but in all casesthey are greater than 25 percent. In the case of heavy neutrino the effect ismuch larger (a factor of 3). Combining out results with the best presentlyavailable experimental limits on the half-life of the neutrinoless double betadecay we have extracted new limits on the effective neutrino mass (light andheavy) and the effective Majoron coupling constant.
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