Results from a Low-Energy Analysis of the CDMS II Germanium Data

TL;DR

This paper presents a reanalysis of CDMS II germanium detector data with a lower energy threshold, improving sensitivity to low-mass WIMPs and setting new constraints that challenge previous potential signals.

Contribution

It introduces a reanalysis method with a 2 keV threshold, enhancing detection sensitivity for WIMPs below 10 GeV/c^2 and providing stronger constraints than earlier results.

Findings

Stronger constraints on WIMPs below 9 GeV/c^2

Excludes parameter space suggested by DAMA/LIBRA and CoGeNT

Improved sensitivity through lowered energy threshold

Abstract

We report results from a reanalysis of data from the Cryogenic Dark Matter Search (CDMS II) experiment at the Soudan Underground Laboratory. Data taken between October 2006 and September 2008 using eight germanium detectors are reanalyzed with a lowered, 2 keV recoil-energy threshold, to give increased sensitivity to interactions from Weakly Interacting Massive Particles (WIMPs) with masses below ~10 GeV/c^2. This analysis provides stronger constraints than previous CDMS II results for WIMP masses below 9 GeV/c^2 and excludes parameter space associated with possible low-mass WIMP signals from the DAMA/LIBRA and CoGeNT experiments.