Related papers: Difficulties in using the sharp neutrino spectrum …
The neutron, besides its $\beta$-decay $n\to p e\bar\nu_e$, might have a new decay channel $n\to n' X$ into mirror neutron $n'$, its nearly mass degenerate twin from parallel dark sector, and a massless boson $X$ which can be ordinary and…
We discuss the size of an electron neutrino wave packet emerging from an electron capture decay using the formalism of open quantum systems. This quantitative result is based on methodology that we have previously used to predict the width…
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…
Despite their high relative abundance in our Universe, neutrinos are the least understood fundamental particles of nature. They also provide a unique system to study quantum coherence and the wavelike nature of particles in fundamental…
We note that detector depth can influence the decay path length available for the primary and secondary particles that are the source of atmospheric neutrinos. As a consequence there is a location dependent modulation to the neutrino flux,…
The threshold displacement energy in solid state detector materials varies from several eV to ~100 eV. If a stable or long lived defect is created as a result of a nuclear recoil event, some part of the recoil energy is stored in the…
The turn of the 21st century witnessed a sudden shift in our fundamental understanding of particle physics. While the minimal Standard Model predicts that neutrino masses are exactly zero, the discovery of neutrino oscillations proved the…
If dark matter decays into electrons and positrons, it can affect Galactic radio emissions and the local cosmic ray fluxes. We propose a new, more general analysis of constraints on dark matter. The constraints can be obtained for any…
Long-lived particles (LLPs) provide an interesting window into physics beyond the Standard Model, offering characteristic signatures at colliders and in cosmology. In this work, we investigate LLPs decays into dark matter. If the lifetime…
The present experimental data on neutrino oscillations, neutrinoless double beta decay and tritium beta decay are collected together and possible mass ranges for Dirac and Majorana neutrinos are found. Four future experimental situations…
Supernova neutrinos have several exceptional features which can lead to interesting physical consequences. At the production point their wave packets have an extremely small size $\sigma_x \sim 10^{-11}$ cm; hence the energy uncertainty can…
The cold dark matter may be in a meta-stable state and decays to other particles with a very long lifetime. If the decaying products of the dark matter are weakly interacting, e.g. neutrinos, then it would have little impact on…
Secondary photons from decays of metastable neutralinos can contribute to the ultra-high energy cosmic ray flux. The neutralino production rate is too low in acceleration mechanisms to affect the cosmic ray spectrum without emitting…
We consider some consequences of the presence of a cosmological lepton asymmetry in the form of neutrinos. A relic neutrino degeneracy enhances the contribution of massive neutrinos to the present energy density of the Universe, and…
We report new experimental limits on the \pi^0 -> \gamma X decay of the neutral pion into a photon and a light boson X followed by the decay X -> e+e-. If this process exist, one would expect a flux of high energy X's produced from \pi^0's…
The brief review of modern theoretical models describing the process of the photon absorption by nucleons at superhigh energies of real photons is given. The main aim of the work is an estimation of the theoretical uncertainty of the cross…
The absorption and extinction spectra of sub-wavelength cylinder arrays are shown to present two different kind of resonances. Close to the Rayleigh anomalies, the diffractive coupling with the lattice periodicity leads to sharp peaks in…
We explore, mostly using data from solar neutrino experiments, the hypothesis that the neutrino mass eigenstates are unstable. We find that, by combining $^8$B solar neutrino data with those on $^7$Be and lower-energy solar neutrinos, one…
Discrepancies from in-beam and in-bottle type experiments measuring the neutron lifetime are on the 4$\sigma$ standard deviation level. In a recent publication Fornal and Grinstein proposed that the puzzle could be solved if the neutron…
If dark matter decays or annihilates into electrons and positrons, it can affect radiation and cosmic-ray backgrounds. We review a novel, more general analysis of constraints on decaying dark matter models, by introducing the response…