Investigating Leggett-Garg inequality in neutrino oscillations -- role of decoherence and decay

Abstract

Neutrinos, due to their weakly interacting nature, provide us with a unique opportunity to test foundations of quantum mechanics over macroscopic distances. There has been considerable theoretical and experimental interest in examining the extent of violation of Leggett-Garg inequalities (LGI) in the context of neutrino flavour oscillations. While it is established that neutrino oscillations occur due to mass and mixing among the three generations of neutrinos, sub-dominant effects due to physics beyond the Standard Model (SM) are not yet ruled out. As we are entering the precision era in neutrino physics, it is possible that some of these effects may leave an imprint on data. Thus, it is worthwhile to investigate different physics scenarios beyond the SM and study their impact on oscillation probabilities. In the present work, we invoke damping effects (including decoherence and decay) on oscillation probabilities and study their implications on the LGI.

Damping signatures at JUNO, a medium-baseline reactor neutrino oscillation experiment

“…Damping signatures can be induced by a class of new physics models. Here, we focus on the exponential damping framework [13,14], i.e., they can be written in the form of multiplying each term of the neutrino oscillation probabilities with exponential factors, which can arise from an approximation of the first-or second-order perturbations to the standard neutrino oscillation probabilities from new physics scenarios [25][26][27]. In this framework, the general expression for the probability of ν a oscillating into ν b in vacuum is given by…”