Dark matter local density determination based on recent observations

TL;DR

This paper reviews methods for determining the local dark matter density, discusses discrepancies in recent Gaia-based estimates, and explores new approaches to improve accuracy in this key astrophysical parameter.

Contribution

It provides a comparative review of existing methods, analyzes reasons for discrepancies, and discusses recent innovative approaches to refine local dark matter density measurements.

Findings

Different methods yield inconsistent estimates.

Discrepancies may arise from data interpretation and model assumptions.

New approaches show promise in resolving current uncertainties.

Abstract

The local density of dark matter is an important quantity. On the one hand, its value is needed for dark matter direct detection searches. On the other hand, a precise and robust determination of the local dark matter density would help us learn about the shape of the dark matter halo of our Galaxy, which plays an important role in dark matter indirect detection searches, as well as in many studies in astrophysics and cosmology. There are different methods available to determine the local dark matter density. Among them, it is common to study either the vertical kinematics of a selected group of tracers or the rotation curve of the Milky Way. Recent estimates of the local dark matter density have used the precise observations conducted by the ESA/Gaia mission. However, in spite of the quality of the data released by Gaia's observations, different analyses of the local dark matter density produce dissimilar results. After a brief review of the most common methods to estimate the local density of dark matter, here we argue about different explanations for the discrepancies in the results of recent analyses. We finish by presenting new approaches that have been proposed in the literature and could help us improve our knowledge of this important quantity.