Radiation Background Studies for 0$\nu\beta\beta$ decay in $^{124}$Sn

TL;DR

This study assesses radiation backgrounds affecting neutrinoless double beta decay detection in $^{124}$Sn, using experimental and simulation methods to estimate neutron flux and propose shielding solutions.

Contribution

It provides new measurements and simulations of neutron-induced backgrounds for $^{124}$Sn decay experiments, and proposes an effective shielding configuration.

Findings

Neutron flux from rock interactions estimated via MC simulations.

Neutron-induced backgrounds characterized using fast neutron activation.

A two-layer borated paraffin and lead shield reduces neutron flux effectively.

Abstract

Radiation background studies pertaining to $0\nu\beta\beta$ decay in $^{124}$Sn have been carried out. A TiLES setup has been installed at TIFR for this purpose. Neutron-induced background is studied in the TIN.TIN detector materials using fast neutron activation technique. The neutron flux ($E_n\leq15$ MeV) resulting from SF and ($\alpha, n$) interactions for the rock in the INO cavern is estimated using MC simulations. A two layer composite shield of borated paraffin (20 cm) + Pb (5 cm) is proposed for the reduction of neutron flux.