A comparison between the low-energy spectra from CoGeNT and CDMS

Abstract

A side-to-side comparison is established between the nuclear recoil energy spectrum from CDMS germanium bolometers and its low-energy equivalent for events in the inner bulk volume of a CoGeNT germanium diode. Acknowledging the orthogonality of the background cuts possible with each type of detector and following an examination of the uncertainties in these searches, a suggestive agreement between these spectra is observed.

Figures (1)

• Figure 1: CDMS SUF (black dots) and Soudan (blue circles) recoil-like spectra, adapted from soudansuf. Red dotted line: expectations from a light-WIMP candidate (m$_{\chi}\sim$7 GeV/c$^{2}$, $\sigma_{SI}\sim1.4\times10^{-4}$ pb) able to induce DAMA/LIBRA and CoGeNT anomalies danandco. Red solid line: best fit to a WIMP of this mass in CoGeNT cogent2. Inset: equivalent ionization spectra using a 17% quenching factor blas. Red dots: CoGeNT spectrum after removal of L-shell EC peak and constant background components cogent2. Blue dots: Soudan CDMS spectrum following the energy shift discussed in the text. A new online version of soudan acknowledges an even larger shift ($\times$1.7) at threshold. Vertical error bars are statistical, horizontal are energy binning. See text for discussion of other uncertainties.