# Constraining the Effective Mass of Majorana Neutrino with Sterile Neutrino Mass for Inverted Ordering Spectrum

Singh, Jaydip  (Department of Physics, Lucknow University, Lucknow 226007, India)

06 May 2019

Abstract: Inspired by the experimental anomalies in neutrino physics and recent oscillation data from short baseline and another neutrino experiment, the realization of one extra neutrino flavor seems to be favoring. This extra flavor may change the observable, $|{m}_{\beta \beta }|$ , of current data taking and next-generation $\left(\beta \beta {\right)}_{\mathrm{0}\nu }$ -decay experiments aim to probe and possibly look at the Inverted Ordering region ( $|{m}_{\beta \beta }|\simeq \mathrm{1}{\mathrm{0}}^{-\mathrm{2}}$ eV) of parameter space. This observation would allow establishing physics beyond the standard model and phenomena like lepton number violation and Majorana nature of neutrino. The range of this observable ( $|{m}_{\beta \beta }|$ ) is not very well defined for both the ordering of mass spectrum (Normal Ordering and Inverted Ordering). Several attempts have been made for defining exactly the range for three active neutrino states. For contrasting this range, I have worked with an extra mass state, ${\nu }_{\mathrm{4}}$ , and its effect on the observable with various combinations of CP violation Majorana phases by taking into account the updated data on the neutrino oscillation parameters for IO case. Based on the Monte Carlo technique, a parameter region is obtained using the fourth Majorana-Dirac phase of sterile parameters that lead to an effective mass below 0.01 eV or .05 eV for inverted mass ordering case which is planned to be observed in the near future experiment.

Published in: Advances in High Energy Physics 2019 (2019) 4863620