Reproducing the DAMA/LIBRA phase-2 results with two dark matter components [CL]

http://arxiv.org/abs/1804.08437


Recently the DAMA/LIBRA collaboration released the long-waited phase-2 results with a lower energy threshold. It was recently argued that a one-component dark matter explanation of the observed annual modulation is strongly disfavoured or excluded unless isospin-violating couplings are invoked. In this short letter, we make the observation that dark matter comprising both a light and a heavy state can reproduce the observed spectrum without the need to invoke fine-tuned isospin-violating couplings. We perform a fit to scenarios with two-component dark matter and find that they are indeed in excellent agreement with the data. Our results show that two qualitatively different solutions are possible in the simplest case of isospin-conserving couplings with equal cross sections (or energy densities) of the two components. The p-values of the best-fit points of the two-component scenarios are equal, or better than, those of the one-component isospin-violating case. We also find very good agreement in the case of general two-component dark matter models.

Read this paper on arXiv…

J. Herrero-Garcia, A. Scaffidi, M. White, et. al.
Fri, 27 Apr 18
-7/64

Comments: 14 pages, 2 figures, 3 tables. Minor changes. References added, typos fixed, and some discussions improved