The Igex 76ge Neutrinoless Double-Beta Decay Experiment: Prospects for   Next Generation Experiments
  The International Germanium Experiment (IGEX) has analyzed 117 mole yr of 76Ge data from its isotopically enriched (86% 76Ge) germanium detectors. Applying pulse-shape discrimination (PSD) to the more recent data, the lower bound on the half-life for neutrinoless double-beta decay of 76Ge is: $T_{1/2}(0\nu)> 1.57 \times 10^{25}$ yr (90% C.L.). This corresponds to an upper bound in the Majorana neutrino mass parameter,$<m_{\nu}>$, between 0.33 eV and 1.35 eV, depending on the choice of theoretical nuclear matrix elements used in the analysis. 
C. E. Aalseth, F. T. Avignone III, R. L. Brodzinski, S. Cebrian, E.   Garcia, D. Gonzalez, W. K. Hensley, I. G. Irastorza, I...