Related papers: Neutron disappearance inside the nucleus
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 perform a direct finite nucleus calculation of the partial width of a bound Delta isobar decaying through the non-mesonic decay mode, Delta N -> NN. This transition is modeled by the exchange of the long ranged pi meson and the shorter…
The neutron beta-decay lifetime plays an important role both in understanding weak interactions within the framework of the Standard Model and in theoretical predictions of the primordial abundance of 4He in Big Bang Nucleosynthesis. In…
We discuss decays of ultra-relativistic neutrinos over cosmological distances by solving the decay equation in terms of its redshift dependence. We demonstrate that there are significant conceptual differences compared to more simplified…
Present limits on neutrino masses are briefly reviewed, along with cosmological and astrophysical hints from dark matter, solar and atmospheric neutrino observations that suggest neutrino masses. These would imply many possible new…
Models that postulate the existence of hidden sectors address contemporary questions, such as the source of baryogenesis and the nature of dark matter. Among the possible mixing processes, neutron-to-hidden-neutron oscillations have been…
Nuclear double beta decay, an extremely rare radioactive decay process, is - in one of its variants - one of the most exciting means of research into particle physics beyond the standard model. The large progress in sensitivity of…
The $^{11}$Be neutron halo nucleus appears to decay into $^{10}$Be with a rate that exceeds expectations. Neutron disappearance into dark matter, beta decay of a halo neutron, or beta-delayed proton decay have been offered as explanations.…
We calculate the lifetime of the deuteron from dimension-six quark operators that violate baryon number by one unit. We construct an effective field theory for $|\Delta B|=1$ interactions that give rise to nucleon and $\Delta B=1$ deuteron…
We use the field theoretical model to perform relativistic calculations of neutrino energy losses caused by the direct Urca processes on nucleons in the degenerate baryon matter. By our analysis, in a free nucleon gas under beta…
We have studied the decay of the \phi meson in nuclear matter by taking into account the renormalization of the K and \bar{K} mesons in the medium. We separate the contribution of the total width into different reaction channels, K\bar{K}…
Precision measurements of neutron decay offer complementary access to particle physics at small distance scales or high energies. In particular they allow tests of the V-A structure of the weak interaction. Among many experimental…
We discuss our recently proposed interpretation of the discrepancy between the bottle and beam neutron lifetime experiments as a sign of a dark sector. The difference between the outcomes of the two types of measurements is explained by the…
We present a new channel of the neutrinoless double beta decay. In this scenario neutrinos not only oscillate inside the nucleus but also interact with an external non-uniform magnetic field. We assume that the field rotates about the…
Neutrino visible decay in the presence of matter is re-evaluated. We study these effects in two future long-baseline experiments where matter effects are relevant: DUNE (1300 km) and a hypothetical beam aimed towards ANDES (7650 km). We…
Recent theoretical work has explored dark matter accumulation in the Earth and its drift towards the center of the Earth that, for the current age of the Earth, does not necessarily result in a concentration of dark matter ($\chi$) in the…
We discuss the phenomenological implications of the neutron (n) oscillation into the mirror neutron (n'), a hypothetical particle exactly degenerate in mass with the neutron but sterile to normal matter. We show that the present…
Study of the neutrinoless $\beta\beta$ decay allows us to put a stringent limit on the effective neutrino Majorana mass, a quantity of fundamental importance. To test our ability to evaluate the nuclear matrix elements that govern the decay…
We point out the following astrophysical consequences of a tau neutrino with mass in the MeV range: (i) if it has a small electric charge which will allow it to become a cold dark matter of the universe, then present limits on the 511 KeV…
The simultaneous beta decay of two neutrons in a nucleus without the emission of neutrinos (called neutrinoless double beta decay) is a lepton number violating process which is not allowed in the Standard Model of particle physics. More…