相关论文: A note on the two-neutrino decay mode of excited n…
We analyze the time evolution of a two-level system prepared in a superposition of its ground state and radiatively unstable excited state. We show that by choosing appropriate means of detection of the radiated field, we can steer the…
A brief review on double beta decay to excited states of daughter nuclei is given. The ECEC(ov) transision to the excited states are discussed in association with a possible enhancement of the decay rate by several orders of magnitude.
A brief review of double beta decay to the excited states of daughter nuclei is given. Results of the most sensitive experiments are presented.
Decay mode of the $2_1^+$ resonant state of $^6$He populated by the $^6$He breakup reaction by $^{12}$C at 240 MeV/nucleon is investigated. The continuum-discretized coupled-channels method is adopted to describe the formation of the…
We study the dynamics of an atomic two-level system decaying by spontaneous emission of light. Subject to continuous detection of the radiated field, the system tends with certainty to the ground state in the long time limit, but at initial…
If neutrinos have masses and mixings, in general some will decay. In models with new particles and new couplings, some decay modes can be fast enough to be of phenomenological interest.
The particle unbound $^{26}$O nucleus is located outside the neutron drip line, and spontaneously decays by emitting two neutrons with a relatively long life time due to the centrifugal barrier. We study the decay of this nucleus with a…
In rather general terms the long term perspective of double beta decay is discussed. All important experimental parameters are investigated as well as the status of nuclear matrix element issues. The link with other neutrino physics results…
The radiative decay of ultrarelativistic massive neutrino $\nu_i \rightarrow \nu_j \gamma$ is investigated in electromagnetic fields in the framework of the Standard Model with lepton mixing. Estimates of the decay probability and ``decay…
Photo nuclear reactions are shown to be used for studying neutrino/weak nuclear responses involved in astro-neutrino nuclear interactions and double beta decays. Charged current weak responses for ground and excited states are studied by…
A new mechanism of nuclear excitation via two-photon electron transitions (NETP) is proposed and studied theoretically. As a generic example, detailed calculations are performed for the $E1E1$ $1s2s\,^1S_0 \rightarrow 1s^2\,^1S_0$…
The pseudo SU(3) model is used to study the double beta decay of Nd150 to the ground and excited states of Sm150 . Low lying collective excitations of Sm150 and its BE(2) intensities are well reproduced. Expressions for the two neutrino…
We examine the effect of excited neutrinos on the annihilation of relic neutrinos with ultra high energy cosmic neutrinos for the $\nu \bar{\nu}\to \gamma\gamma$ process. The contribution of the excited neutrinos to the neutrino-photon…
We study the ground and excited resonance states of $^{26}$O with a three-body model of $^{24}$O+n+n taking into account the coupling to the continuum. To this end, we use the new experimental data for the invariant mass spectroscopy of the…
We study the possibility that the three mass states of the ordinary active neutrinos actually split into pairs of quasi-degenerate states, with $\Delta m^2_{kk'} \sim 10^{-12}$ eV$^2$ or less, as a result of mixing of active neutrinos with…
The fluctuation properties of nuclear giant resonance spectra are studied in the presence of continuum decay. The subspace of quasi-bound states is specified by one-particle one-hole and two-particle two-hole excitations and the continuum…
The two-particle wave function of neutrino and antineutrino after the decay of a Z boson is found as a solution of an initial value problem. The wave packet of this state involves the coherent superposition of massive neutrinos and…
Two-photon decay rates in simple atoms such as hydrogenlike systems represent rather interesting fundamental problems in atomic physics. The sum of the energies of the two emitted photons has to fulfill an energy conservation condition, the…
The pseudo SU(3) approach is used to describe low lying states and BE(2) intensities of rare earth and actinide nuclei which are double beta decay candidates. The double beta half lives of some of these nuclei to the ground and excited…
The relativistic and nonrelativistic approaches for the calculations of the two-photon decay rates of highly excited states in hydrogen are compared. The dependence on the principal quantum number (n) of the ns, nd, and np initial states is…