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    Calculation of nuclear matrix elements in neutrinoless double electron capture

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    We compute nuclear matrix elements for neutrinoless double electron capture on 152^{152}Gd, 164^{164}Er and 180^{180}W nuclei. Recent precise mass measurements for these nuclei have shown a large resonance enhancement factor that makes them the most promising candidates for observing this decay mode. We use an advanced energy density functional method which includes beyond mean-field effects such as symmetry restoration and shape mixing. Our calculations reproduce experimental charge radii and B(E2)B(E2) values predicting a large deformation for all these nuclei. This fact reduces significantly the values of the NMEs leading to half-lives larger than 102910^{29} years for the three candidates

    Effective theories and constraints on new phyhsics

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    Anomalous moments of the top quark arises from one loop corrections to the vertices tˉtg\bar t t g and tˉtγ\bar t t \gamma. We study these anomalous couplings in different frameworks: effective theories, Standard Model and 2HDM. We use available experimental results in order to get bounds on these anomalous couplings.Comment: 8 pages, 2 figures, talk presented by R. Martinez at the X Mexican School of Particles and Fields, Playa del Carmen, Mexico, 200
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