arXiv:1401.3295·v1·Cosmology and Nongalactic Astrophysics
Search for An Annual Modulation in Three Years of CoGeNT Dark Matter Detector Data
C.E. Aalseth🇺🇸 · P.S. Barbeau🇺🇸 · J. Colaresi🇺🇸 · J.I. Collar🇺🇸 · J. Diaz Leon🇺🇸 · J.E. Fast🇺🇸 · N.E. Fields🇺🇸 · T.W. Hossbach🇺🇸 · A. Knecht🇺🇸 · M.S. Kos🇺🇸 · M.G. Marino🇺🇸 · H.S. Miley🇺🇸
Abstract
Weakly Interacting Massive Particles (WIMPs) are well-established dark matter candidates. WIMP interactions with sensitive detectors are expected to display a characteristic annual modulation in rate. We release a dataset spanning 3.4 years of operation from a low-background germanium detector, designed to search for this signature. A previously reported modulation persists, concentrated in a region of the energy spectrum populated by an exponential excess of unknown origin. Its phase and period agree with phenomenological expectations, but its amplitude is a factor 4-7 larger than predicted for a standard WIMP galactic halo. We consider the possibility of a non-Maxwellian local halo velocity distribution as a plausible explanation, able to help reconcile recently reported WIMP search anomalies.
Comments: Three datasets and note on usage included as ancillary files