Related papers: What can we learn from recent $2\nu\beta\beta$ exp…
For the first time, half-lives and energy spectra of forbidden $\beta$ decays are calculated within the realistic shell model. Namely, we approach this issue starting from a realistic nucleon-nucleon potential and deriving effective…
Study of the neutrinoless double beta decay, $0\nu\beta\beta$, includes a variety of problems of nuclear structure theory. They are reviewed here. The problems range from the mechanism of the decay, i.e. exchange of the light Majorana…
We study two-neutrino ($2\nu\beta\beta$) and neutrinoless double-$\beta$ ($0\nu\beta\beta$) decays in the nuclear shell model and proton-neutron quasiparticle random-phase approximation (pnQRPA) frameworks. Calculating the decay half-life…
Neutrinoless double beta decay, if observed, could distinguish whether neutrino is a Dirac or a Majorana particle, and it could be used to determine the absolute scale of the neutrino masses. $^{136}$Xe is one of the most promising…
The nuclear matrix elements $M^{0\nu}$ of the neutrinoless double beta decay ($0\nu\beta\beta$) are evaluated for $^{76}$Ge,$^{100}$Mo, $^{130}$Te, and $^{136}$Xe within the Renormalized Quasiparticle Random Phase Approximation (RQRPA) and…
We use the large scale nuclear shell model to calculate the nuclear matrix elements for the neutrino mediated neutrinoless double beta decay within the Left-Right symmetric model for four nuclei: $^{76}$Ge, $^{82}$Se, $^{130}$Te and…
Theoretical estimates for the half life of neutrinoless double beta decay in candidate nuclei are affected by both particle and nuclear physics uncertainties, which may complicate the interpretation of decay signals or limits. We study such…
The nucleus is an extraordinarily complex object where fundamental forces are at work. The solution of this many-body problem has challenged physicists for decades: several models with complementary virtues and flaws have been adopted, none…
Nuclear double beta decay provides an extraordinarily broad potential to search for beyond Standard Model physics, probing already now the TeV scale, on which new physics should manifest itself. These possibilities are reviewed here. First,…
We developed the quasi-particle random phase approximation (QRPA) for the neutrino scattering off even-even nuclei via neutral current (NC) and charged cur- rent (CC). The QRPA has been successfully applied for the \beta and \beta\beta…
All existing positive results on two-neutrino double beta decay and two-neutrino double electron capture in different nuclei have been analyzed. Weighted average and recommended half-life values for $^{48}$Ca, $^{76}$Ge, $^{82}$Se,…
Four nuclei which are proved to be $2\nu\beta\beta$ emitters ($^{76}$Ge, $^{82}$Se, $^{150}$Nd, $^{238}$U), and four suspected, due to the corresponding Q-values, to have this property ($^{148}$Nd, $^{154}$Sm, $^{160}$Gd, $^{232}$Th), were…
We have recently developed a nuclear model, which is a natural extension of the $pn$-QRPA model, specially designed to describe double charge exchange (DCE) processes generated by two-body DCE transition operators. It is based on the…
Nuclear double beta decay provides an extraordinarily broad potential to search for beyond Standard Model physics, probing already now the TeV scale, on which new physics should manifest itself. These possibilities are reviewed here. First,…
Neutrinoless double beta decay (0{\nu}\b{eta}\b{eta}) is considered the best potential resource to determine the absolute neutrino mass scale. Moreover, if observed, it will signal that the total lepton number is not conserved and neutrinos…
We study two-neutrino double-beta decay ($2\nu\beta\beta$) into first-excited $0^+_2$ states of nuclei used in $\beta\beta$ decay experiments, including $^{76}$Ge, $^{82}$Se, $^{130}$Te, and $^{136}$Xe. We calculate the corresponding…
Neutrinoless double-beta ($0 \nu \beta \beta$) decay is a promising beyond Standard Model process. Two-neutrino double-beta ($2 \nu \beta \beta$) decay is an associated process that is allowed by the Standard Model, and it was observed in…
Double-beta decay matrix elements (ME) for $^{76}Ge$ are calculated with different quasi random phase approximation (QRPA)-based methods. First, the ME for the two-neutrino mode are computed using two choices for the single particle (s.p.)…
We investigate two-neutrino double beta decay ($2\nu\beta\beta$) in chiral effective field theory. We find contributions from weak magnetism and double-weak pion-exchange at next-to-leading-order in the chiral power counting. We discuss the…
We recently proposed a new method to calculate the standard nuclear matrix elements for neutrinoless double-$\beta$ decay ($0\nu\beta\beta$) of ${}^{48}$Ca going beyond the closure approximation. Here we extend this analysis to the…