We derive for the first time an effective neutrino evolution Hamiltonian accounting for neutrino interactions with external magnetic field due to neutrino charge radii and anapole moment. The results are interesting for possible applications in astrophysics.
In our previous studies (see [1] and references therein) we developed a new theoretical framework that enabled one to consider a new mechanism of neutrino quantum decoherence engendered by the neutrino radiative decay. In parallel, another framework was developed (see [2] and references therein) for the description of the neutrino quantum decoherence due to the non-forward neutrino scattering processes. Both mechanisms are described by the master equations in the Lindblad form. We study the influence of the neutrino quantum decoherence on collective neutrino oscillations. In the present studies we are are not interested in a specific mechanism of neutrino quantum decoherence. Therefore, we use the general Lindblad master equation for the description of the neutrino quantum decoherence and do not fix an analytical expressions for the decoherence and relaxation parameters.
We have derived a new method which allows to compute the full and the Pauli reference kinetic potentials for atoms and molecules in a real space representation. This is done by applying the optimized effective potential (OEP) method to {the} Kohn-Sham non-interacting kinetic energy expression. Additionally, we have also derived a simplified OEP variant based on the common energy denominator approximation which has proven to give much more stable and robust results than the original OEP one. Moreover, we have also proved that at the solution point our approach is formally equivalent to the commonly used Bartolotti-Acharya formula.
The phenomena of particle mixing and flavor oscillations in elementary particle physics can be addressed by the point of view of quantum information theory, and described in terms of multi-mode entanglement of single-particle states. In this paper we show that such a description can be extended to the domain of quantum field theory, where we uncover a fine structure of quantum correlations associated with multi-mode, multi-particle entanglement. By means of an entanglement measure based on the linear entropies associated with all the possible bipartitions, we analyze the entanglement in the states of flavor neutrinos and anti-neutrinos. Remarkably, we show that the entanglement is connected with experimentally measurable quantities, i.e. the variances of the lepton numbers and charges.
We study the effects of violation of the equivalence principle (VEP) or violation of Lorentz invariance (LIV) in the neutrino sector on the asymmetry between T-conjugate oscillation probabilities, $Delta P_T equiv P( u_{alpha} to u_{beta}) - P( u_{beta} to u_{alpha})$, in a three-flavour framework. We find that additional mixing due to these mechanisms, while obeying all present bounds, can lead to an observable enhancement, suppression, and/or sign change in $Delta P_T$ for the preferred energies and baselines of a neutrino factory. The measurement of this asymmetry can be used to establish a new upper limit of order $10^{-26}$ on VEP or LIV in the $( u_e, u_mu)$ and $( u_e, u_tau)$ sectors.