Probing the effects of scalar Non Standard Interactions at Long Baseline Experiments

Abstract

Neutrino oscillations which essentially confirms neutrinos have non zero masses, is the first hint of physics beyond the Standard Model (SM). When neutrinos propagates through matter it interacts with the matter via weak interactions mediating a W or Z bosons. The study of Beyond Standard Model (BSM) physics often comes with some additional unknown coupling of neutrinos termed as non standard interactions(NSIs). Wolfenstein was the first to point out this type of NSIs of neutrinos with a vector field mediated by a vector boson namely vector NSI. There is also a possibility of neutrinos to couple with scalar field, which can offer rich phenomenology in neutrino oscillations. This scalar NSI effect the neutrino mass matrix instead of appearing as a matter potential, which makes its effect interesting to probe it further. In this work, we have explored the effect of scalar NSI at Long Baseline (LBL) Experiment (DUNE). We found that the diagonal elements of scalar NSI matrix can have a significant impact on the oscillation probabilities of DUNE. Also, as it perturbs the neutrino mass term it can fake the CP effect in LBL experiments. As the mass correction due o scalar NSI scales linearly with the matter density scalar NSI can sense the matter density variation and LBL experiments are an excellent candidate to probe it. We found that indeed the impact of scalar NSI on LBL experiments is notable and it needs further exploration to put some constrain on the scalar NSI parameters.