相关论文: Weak Magnetism in Two Neutrino Double Beta Decay
Neutrinoless double beta decay occurs through the magnetic coupling of dimension five, $\lambda_W/m_{\nu*}$, among the excited electron neutrino $\nu^*$, electron and $W$ boson if $\nu^*$ is a massive Majorana neutrino. (\lambda_W m_W /…
The evaluation of the nuclear matrix elements (NME) of the two-neutrino double beta ($2\nu\beta\beta$) decay and neutrinoless double beta ($0\nu\beta\beta$) decay using the proton-neutron quasiparticle random-phase approximation (pnQRPA) is…
We study the effect of deformation on the two-neutrino double beta decay for ground state to ground state transitions in all the nuclei whose half-lives have been measured. Our theoretical framework is a deformed QRPA based in Woods-Saxon…
Results of several double beta decay experiments, performed with the help of low background crystal scintillators, are presented. In particular, the half-life value of the two-neutrino double beta decay of 116-Cd has been measured as 2.9…
A method to calculate the nuclear double beta decay ($2\nu\beta\beta$- and $0\nu\beta\beta$-) amplitudes within the continuum random phase approximation (cQRPA) is formulated. Calculations of the $\beta\beta$ transition amplitudes within…
The existing calculations of the nuclear matrix elements of the neutrinoless double $\beta$-decay differ by about a factor three. This uncertainty prevents quantitative interpretation of the results of experiments searching for this…
A large experimental program is being mounted to search for neutrinoless double-beta decay over the next decade. Multiple experiments using different target isotopes are being prepared to explore the whole parameter space allowed for…
Nuclear matrix elements (NMEs) for two-neutrino double-beta decay ($2\nu\beta\beta$) are studied in the framework of relativistic nuclear energy density functional (REDF). The properties of nuclei involved in the decay are obtained using…
The occurrence of the neutrinoless decay 0n-bb mode has fundamental consequences: first total lepton number is not conserved, and second, the neutrino is a Majorana particle. Further the effective mass measured allows to put an absolute…
A comparison is made of the probability of the process of two neutrino double beta decay for $^{82}$Se in direct (counter) and geochemical experiments. It is shown that the probability is systematically lower in geochemical experiments,…
The search for neutrinoless double beta decay is a rich source for new physics. The observation of this decay will lead to understanding of the absolute mass scale of neutrinos, the Majorana nature of the neutrino (whether the neutrino is…
We give the prediction on the effective Majorana mass for neutrinoless double $\beta$ decay in a simple extension of the Standard Model (nuMSM). The model adds three right-handed neutrinos with masses smaller than the electroweak scale, and…
The proposed Majorana double-beta decay experiment is based on an array of segmented intrinsic Ge detectors with a total mass of 500 kg of Ge isotopically enriched to 86% in 76Ge. A discussion is given of background reduction by: material…
We report the results of a calculation of the nuclear matrix element of neutrinoless double-$\beta$ decay of $^{48}$Ca, carried out taking into account nucleon-nucleon correlations in both coordinate- and spin-space. Our numerical results,…
We discuss the contributions of higher order terms in weak Hamiltonian to the standard two-neutrino double beta decay. The formalism for the unique first forbidden transitions has been developed, and it is shown that they can alter the…
Neutrinoless double-beta decay is a forbidden, lepton-number-violating nuclear transition whose observation would have fundamental implications for neutrino physics, theories beyond the Standard Model and cosmology. In this review, we…
In a previous article [Phys. Rev. D 79, 053001 (2009)] we estimated the correlated uncertainties associated to the nuclear matrix elements (NME) of neutrinoless double beta decay (0 nu beta beta) within the quasiparticle random phase…
The search for neutrinoless double beta decay has internationally been recognized as the most promising approach to determine the Majorana nature of neutrinos. This hypothesized decay would, if observed, violate lepton number in weak…
We report the observation of two-neutrino double-beta decay in Xe-136 with T_1/2 = 2.11 +- 0.04 (stat.) +- 0.21 (sys.) x 10^21 yr. This second order process, predicted by the Standard Model, has been observed for several nuclei but not for…
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…