Probing neutrino decay scenarios by using the Earth matter effects on supernova neutrinos

The observation of Earth matter effects in the spectrum of neutrinos coming from a next galactic core-collapse supernova (CCSN) could, in principle, reveal if neutrino mass ordering is normal or inverted. One of the possible ways to identify the mass ordering is through the observation of the modulations that appear in the spectrum when neutrinos travel through the Earth before they arrive at the detector. These features in the neutrino spectrum depend on two factors, the average neutrino energies, and the difference between the primary neutrino fluxes of electron and other flavors produced inside the supernova. However, recent studies indicate that the Earth matter effect for CCSN neutrinos is expected to be rather small and difficult to be observed by currently operating or planned neutrino detectors mainly because of the similarity of average energies and fluxes between electron and other flavors of neutrinos, unless the distance to CCSN is significantly smaller than the typically expected one, ∼ 10 kpc. Here, we are looking towards the possibility if the non-standard neutrino properties such as decay of neutrinos can enhance the Earth matter effect. In this work we show that invisible neutrino decay can potentially enhance significantly the Earth matter effect for both νe and ν̅e channels at the same time for both mass orderings, even if the neutrino spectra between electron and other flavors of neutrinos are very similar, which is a different feature not expected for CCSN neutrinos with standard oscillation without the decay effect.

Calibrating Einstein field equations using rippling 3-Riemannian structure for gravity with dark matter effects

The paper presents modifications to Einstein field equations (EFEs) based on the model proposed in the working paper, 'Rippling 3-Riemannian structure describing gravity with dark matter effects'. The model proposes matter and energy are separate entities and energy is a property of three dimensional probabilistic structure spanning space. Mass interacts by binding energy density causing variations in length and time scales, mathematically equivalent to spacetime curvature in general relativity. Gravity is thus described as flow and distribution of energy density. Bounded energy density is the additional source of gravity leading to dark matter observations. The results of the model proposes two EFEs for large and largest scales and further predicts dependence of cosmological constant on space and time coordinates.