We report on several features present in the energy spectrum from an ultra low-noise geranium detector operated at 2,100 m.w.e. By implementing a new technique able to reject surface events, a number of cosmogenic peaks can be observed for the first time. We discuss several possible causes for an irreducible excess of bulk-like events below 3 keVee, including a dark matter candidate common to the DAMA/LIBRA annual modulation effect, the hint of a signal in CDMS, and phenomenological predictions. Improved constraints are placed on a cosmological origin for the DAMA/LIBRA effect.
Revised: January 27, 2012 |
Published: April 1, 2011
Citation
Aalseth C.E., P. Barbeau, N.S. Bowden, B. Cabrera-Palmer, J. Colaresi, J.I. Collar, and S. Dazeley, et al. 2011.Results from a Search for Light-Mass Dark Matter with a P-type Point Contact Germanium Detector.Physical Review Letters 106, no. 13:Article No. 131301.PNNL-SA-71421.doi:10.1103/PhysRevLett.106.131301