Mirror dark matter and the new DAMA/LIBRA results: A simple explanation for a beautiful experiment

TL;DR

This paper demonstrates that mirror dark matter, especially a helium prime dominated halo with a small oxygen prime component, can explain the DAMA/LIBRA annual modulation results while remaining consistent with null results from other dark matter detection experiments.

Contribution

The paper provides a re-analysis of mirror dark matter as an explanation for DAMA/LIBRA results, incorporating new data, updated quenching factors, and latest experimental constraints.

Findings

Mirror dark matter can explain DAMA/LIBRA results.

A helium prime dominated halo with a small oxygen prime component suffices.

Alternative hidden sector models can mimic mirror dark matter success.

Abstract

Recently, the DAMA/LIBRA experiment has convincingly confirmed the DAMA/NaI annual modulation signal, experimentally demonstrating the existence of non-baryonic dark matter in the halo of our galaxy. Meanwhile, in another part of town, other experiments such as CDMS and XENON10 have not detected any evidence for dark matter. One promising dark matter candidate which can reconcile the positive DAMA annual modulation signal with the null results from the other experiments, is mirror dark matter. We re-analyse the mirror matter interpretation of the DAMA annual modulation signal utilizing a) the new data from DAMA/LIBRA, including the measured energy dependence of the annual modulation signal b) an updated quenching factor which takes into account the channeling effect in $NaI$ crystals and c) the latest constraints from CDMS/Ge, CDMS/Si and XENON10 experiments. We show that the simplest possibility of a $He'$ (and/or $H'$) dominated halo with a small $O'$ component is sufficient to fully explain all of the dark matter experiments. We also point out that a certain class of hidden sector dark matter models, although theoretically less appealing and less constrained, can mimic the success of the mirror dark matter model and hence are also viable.