DAMIC at SNOLAB

TL;DR

The paper presents the DAMIC CCD detector's low-threshold, uniform response, and imaging capabilities, demonstrating its potential for dark matter detection and background suppression in underground experiments.

Contribution

It introduces the fully-depleted CCD as a sensitive particle detector with low energy threshold and imaging capabilities, and reports initial results from its deployment in SNOLAB.

Findings

Detects ionizing events down to 50 eVee

Uniform energy response and good resolution across silicon

First deployment results at SNOLAB with potential for dark matter detection

Abstract

We introduce the fully-depleted charge-coupled device (CCD) as a particle detector. We demonstrate its low energy threshold operation, capable of detecting ionizing energy depositions in a single pixel down to 50 eVee. We present results of energy calibrations from 0.3 keVee to 60 keVee, showing that the CCD is a fully active detector with uniform energy response throughout the silicon target, good resolution (Fano ~0.16), and remarkable linear response to electron energy depositions. We show the capability of the CCD to localize the depth of particle interactions within the silicon target. We discuss the mode of operation and unique imaging capabilities of the CCD, and how they may be exploited to characterize and suppress backgrounds. We present the first results from the deployment of 250 um thick CCDs in SNOLAB, a prototype for the upcoming DAMIC100. DAMIC100 will have a target mass of 0.1 kg and should be able to directly test the CDMS-Si signal within a year of operation.