DAMA/LIBRA dark matter signal: a global analysis

Abstract

The annual modulation reported by the DAMA/LIBRA collaboration remains in tension with the null results of other direct-detection experiments. We investigate the compatibility of DAMA/LIBRA with LZ, PICO-60 and CDMSlite within a generalized non-relativistic effective field theory (EFT) framework. In addition to the EFT operator expansion we investigate additional modifications to the standard WIMP picture, including inelastic scattering, variations in the NaI quenching factors, and a rescaling of the dark-matter velocity dispersion. We perform a Markov chain Monte Carlo analysis in this extended model space, using two alternative approaches to the likelihood function describing the DAMA/LIBRA data. Both approaches result in strong discrepancy between the data from DAMA/LIBRA and other experiments. We conclude that the extended model space considered here cannot accommodate the DAMA/LIBRA signal while remaining consistent with the non-observation of dark matter in other experiments.