Study of neutron-induced background and its effect on the search of 0$\nu\beta\beta$ decay in $\rm^{124}Sn$

TL;DR

This study investigates neutron-induced backgrounds in the TIN.TIN detector for neutrinoless double beta decay search in $ m^{124}Sn$, analyzing neutron flux, reactions, and material choices to optimize detector sensitivity.

Contribution

It provides a detailed analysis of neutron backgrounds and material effects, informing detector design for more effective neutrinoless double beta decay experiments.

Findings

Teflon is preferable over Torlon due to lower gamma background.

Neutron reactions with Sn isotopes contribute near the $Q_{etaeta}$ energy.

Neutron flux and reaction data inform background mitigation strategies.

Abstract

Neutron-induced background has been studied in various components of the TIN.TIN detector, which is under development for the search of Neutrinoless Double Beta Decay in $\rm^{124}Sn$. Fast neutron flux $\sim10^{6}~n~cm^{-2}s^{-1}$ covering a broad energy range ($ \sim0.1$ to $ \sim18$~MeV) was generated using $^{9}Be(p,n)^{9}B$ reaction. In addition, reactions with quasi-monoenergetic neutrons were also studied using $^{7}Li(p,n)^{7}Be$ reaction. Among the different cryogenic support structures studied, Teflon is found to be preferable compared to Torlon as there is no high energy gamma background ($E_\gamma >$ 1 MeV). Contribution of neutron-induced reactions in $\rm ^{nat, 124} $Sn from other Sn isotopes (A = 112 -- 122) in the energy region of interest, namely, around the $Q_{\beta\beta}$ of $\rm^{124}Sn$ ($E \sim$ 2.293 MeV), is also investigated.