2012/03/31 by D. Barker, D. -M. Mei, D.-M. Mei +1 · 1 citation
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #Particle Detector Development and Performance #Particle physics theoretical and experimental studies #astro-ph.IM #hep-ex #nucl-ex
paper · pdf · doi:10.1016/j.astropartphys.2012.08.006
17 pages and 8 figures
arxiv created 2012/08/22 · openalex publication_date 2012/09/01 · arxiv updated 2015/06/04 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The discrepancies in claims of experimental evidence in the search for weakly interacting massive particle (WIMP) dark matter necessitate a model for ionization efficiency (the quenching factor) at energies below 10 keV. We have carefully studied the physics processes that contribute to the ionization efficiency through stopping power. The focus of this work is the construction of a model for the ionization efficiency in germanium by analyzing the components of stopping power, specifically that of the nuclear stopping power, at low energies. We find a fraction of the ZBL nuclear stopping power can contribute to ionization efficiency. We propose a model that corrects the missing contribution to ionization efficiency from the ZBL nuclear stopping power. The proposed model is compared to previous measurements of ionization efficiency in germanium as well as that of other theoretical models. Using this new model, the thresholds of both CDMS II and CoGeNT are analyzed and compared in terms of the nuclear recoil energy.