Scintillation characteristics of a NaI(Tl) crystal at low-temperature with silicon photomultiplier

TL;DR

This study investigates how the scintillation properties of NaI(Tl) crystals change at low temperatures when coupled with silicon photomultipliers, highlighting potential for dark matter detection.

Contribution

It provides the first detailed measurement of NaI(Tl) scintillation characteristics at low temperatures with SiPMs, demonstrating increased light yield near 230K.

Findings

20% increase in light yield at 230K

NaI(Tl) with SiPM is promising for dark matter detectors

Decays times and light outputs vary with temperature

Abstract

Scintillation characteristics of a thallium doped sodium iodide (NaI(Tl)) crystal with a dimension of 0.6 x 0.6 x 2 cm3 are studied by attaching a silicon photomultiplier (SiPM) direct to the crystal over a temperature range from 93 to 300 K. The scintillation light output and decay time are measured by irradiating 59.54 keV gamma-rays from a 241Am source. We observed approximately 20% increase in light yield at 230K compared to that at the room temperature. At this condition, the NaI(Tl) crystal coupled with the SiPM can be a good candidate for future dark matter search detector.