Halo-independence with quantified maximum entropy at DAMA/LIBRA

Abstract

Using the DAMA/LIBRA anomaly as an example, we formalise the notion of halo-independence in the context of Bayesian statistics and quantified maximum entropy. We consider an infinite set of possible profiles, weighted by an entropic prior and constrained by a likelihood describing noisy measurements of modulated moments by DAMA/LIBRA. Assuming an isotropic dark matter (DM) profile in the galactic rest frame, we find the most plausible DM profiles and predictions for unmodulated signal rates at DAMA/LIBRA. The entropic prior contains an a priori unknown regularisation factor, $\beta$, that describes the strength of our conviction that the profile is approximately Maxwellian. By varying $\beta$, we smoothly interpolate between a halo-independent and a halo-dependent analysis, thus exploring the impact of prior information about the DM profile.

16 pages, 6 figures. Matches published version. Comments about isotropy added

References in corpus (5)

• First results from DAMA/LIBRA and the combined results with DAMA/NaI
• New results from DAMA/LIBRA
• Search for Electronic Recoil Event Rate Modulation with 4 Years of XENON100 Data
• Taking Halo-Independent Dark Matter Methods Out of the Bin
• Unified Halo-Independent Formalism From Convex Hulls for Direct Dark Matter Searches