English

Germanium Detector Response to Nuclear Recoils in Searching for Dark Matter

Instrumentation and Methods for Astrophysics 2015-06-04 v4 High Energy Physics - Experiment Nuclear Experiment

Abstract

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.

Keywords

Cite

@article{arxiv.1203.4620,
  title  = {Germanium Detector Response to Nuclear Recoils in Searching for Dark Matter},
  author = {D. Barker and D. -M. Mei},
  journal= {arXiv preprint arXiv:1203.4620},
  year   = {2015}
}

Comments

17 pages and 8 figures