Response of undoped cryogenic CsI to low-energy nuclear recoils

TL;DR

This study measures the quenching factor of undoped cryogenic CsI for low-energy nuclear recoils, demonstrating its potential as a dark matter and neutrino detector due to favorable scintillation properties at liquid nitrogen temperatures.

Contribution

First measurement of quenching factor for undoped cryogenic CsI, showing similarity to sodium-doped CsI and confirming its suitability for rare-event detection.

Findings

Quenching factor is similar to sodium-doped CsI at room temperature.

High light yield and favorable decay properties at 108-165 K.

Potential of undoped cryogenic CsI for dark matter and neutrino detection.

Abstract

The bright scintillation of pure CsI operated at liquid-nitrogen temperature makes of this material a promising dark matter and neutrino detector. We present the first measurement of its quenching factor for nuclear recoils. Our findings indicate it is indistinguishable from that for sodium-doped CsI at room temperature. Additional properties such as light yield, afterglow, scintillation decay properties for electron and nuclear recoils, and energy proportionality are studied over the \mbox{108-165 K} temperature range, confirming the vast potential of this medium for rare-event searches.