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

## TL;DR

This paper investigates how the addition of a sterile neutrino affects the effective Majorana neutrino mass in inverted mass ordering, with implications for neutrinoless double beta decay experiments and physics beyond the standard model.

## Contribution

It introduces a detailed analysis of sterile neutrino effects on the effective mass in inverted ordering, using Monte Carlo simulations with updated oscillation data.

## Key findings

- Sterile neutrino presence can lower the effective mass below 0.01 eV.
- Parameter regions identified where effective mass is below 0.05 eV.
- Results are relevant for upcoming neutrinoless double beta decay experiments.

## 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 seem to be favoring. This extra flavor may change the observable, $|m_{\beta\beta}|$ of currently data taking and next-generation $(\beta\beta)_{0\nu}$-decay experiments aim to probe and possibly look the Inverted Ordering region($|m_{\beta\beta}| \simeq 10^{-2}$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 states, $\nu_{4}$ and its effect on the observable with various combination 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.