ASTAROTH: A Novel Detector for Dark Matter Direct Detection Using Cryogenic SiPMs

TL;DR

ASTAROTH introduces a cryogenic SiPM-based NaI(Tl) detector with higher efficiency and lower noise, advancing dark matter detection capabilities beyond traditional PMT-based systems.

Contribution

The paper presents the first characterization of a NaI(Tl) detector using cryogenic SiPMs, demonstrating improved detection efficiency and reduced noise for dark matter searches.

Findings

Achieved 4.5 photoelectrons/keV with SiPM readout

Demonstrated feasibility of cryogenic SiPMs for NaI(Tl) detectors

Reduced dark noise by two orders of magnitude

Abstract

The DAMA experiment's long-standing claim of dark matter detection remains a key open issue in astroparticle physics. Independent verification requires NaI(Tl)-based detectors with enhanced low-energy sensitivity. Current detectors rely on photomultiplier tubes (PMTs) which features limited detection efficiency, intrinsic radioactivity, and high noise at keV energies. ASTAROTH is an R&D project that developed a proof of concept NaI(Tl) detector where siliconphotomultipliers (SiPMs) have been used instead of PMTs, offering higher photon detection efficiency, negligible radioactivity, and, most of all, a reduction of two orders of magnitude in the dark noise. The setup includes a custom cryostat operating at approximately 80 K. We report the first characterization of an approximately 360 g NaI(Tl) crystal coupled to a 5 x 5 cm SiPM matrix, yielding 4.5 photoelectrons\keV after crosstalk correction. This promising result demonstrates the feasibility of SiPM-based readout for NaI(Tl) and paves the way for future large-scale dark matter experiments.