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arXiv · 1306.2349

A Spin-Dependent Interpretation for Possible Signals of Light Dark Matter

Abstract

Signals broadly compatible with light (7-10 GeV) dark matter have been reported in three direct detection experiments: CoGeNT, DAMA/LIBRA, and CDMS-II silicon. These possible signals have been interpreted in the context of spin-independent interactions between the target nuclei and dark matter, although there is tension with null results, particularly from xenon-based experiments. In this paper, we demonstrate that the CoGeNT and CDMS-II silicon results are also compatible assuming a spin-dependent neutron interaction, though this is in tension with xenon-based experiments and PICASSO. The tension with the null results from XENON100 and XENON10 is approximately the same as for the spin-independent coupling. All three experimental signals can be made compatible through a combination of spin-dependent interactions with both the proton and neutron, although such a scenario increases the conflict with the null results of other experiments.

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BibTeXRIS

Matthew R. Buckley, W. Hugh Lippincott. 2013-06-10. A Spin-Dependent Interpretation for Possible Signals of Light Dark Matter. https://doi.org/10.1103/physrevd.88.056003

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