Compatibility of DAMA/LIBRA dark matter detection with other searches in light of new Galactic rotation velocity measurements

TL;DR

This paper re-examines DAMA/LIBRA dark matter signals considering new Galactic rotation velocities, finding some parameter regions still compatible with other null results, especially for low-mass WIMPs.

Contribution

It incorporates recent Galactic velocity measurements into the analysis of DAMA data, updating the WIMP parameter space compatibility with other experiments.

Findings

Small WIMP mass region (~7-8 GeV) remains compatible at 3σ.

Compatibility for spin-dependent scattering off protons for 5-15 GeV WIMPs.

Best fit regions shift to lower WIMP masses with new velocity data.

Abstract

The DAMA/NaI and DAMA/LIBRA annual modulation data, which may be interpreted as a signal for the existence of weakly interacting dark matter (WIMPs) in our galactic halo, are re-examined in light of new measurements of the local velocity relative to the galactic halo. In the vicinity of the Sun, the velocity of the Galactic disk has been estimated to be 250 km/s rather than 220 km/s. Our analysis is performed both with and without the channeling effect included. The best fit regions to the DAMA data are shown to move to slightly lower WIMP masses. Compatibility of DAMA data with null results from other experiments (CDMS, XENON10, and CRESST I) is investigated given these new velocities. A small region of spin-independent (elastic) scattering for 7-8 GeV WIMP masses remains at 3$\sigma$. Spin-dependent scattering off of protons is viable for 5-15 GeV WIMP masses for direct detection experiments (but has been argued by others to be further constrained by Super-Kamiokande due to annihilation in the Sun).