Ankur Verma (Texas A&M University)
Mitchell Institute for Fundamental Physics & Astronomy
College Station, Texas 77843
The non-standard interactions (NSI) in the neutrino sector are a well- motivated phenomenological approach to understand the new physics in the neutrino sector. Non standard neutrino-electron interaction mediated by light scalar/vector mediator arises naturally in many low-scale models. We also propose one such new model with a light scalar mediator. We investigate the parameter space of such low-scale models in reactor-based neutrino experiments with low threshold Ge and Si detectors , and find the prospect of probing/ruling out the relevant parameter space by finding the projected sensitivity at 90% confidence level by performing a chi square analysis. Since these interactions with light mediators may involve sub-keV energy transfers, we also include atomic and crystal effects in calculations. We find that a detector capable of discriminating between electron recoil and nuclear recoil signal down to a very low threshold such as 5 eV placed in reactor based experiment would be able to probe a larger region in parameter space compared to the previously explored region. Further, CP violating complex NSIs are also known to explain the slight NOvA and T2K tension in determination of standard CP-phase. We show that the best fits of the light scalar NSI model to the NOvA and T2K data can already be ruled out by the existing experiments but the vector NSI fits still remain unconstrained.