Dark matter local density determination: recent observations and future prospects.

Area of Science:

• Astrophysics
• Cosmology
• Particle Physics

Background:

• The local density of dark matter (ρDM,⊙) is a key parameter for dark matter direct detection experiments.
• Accurate estimation of ρDM,⊙ is essential for interpreting experimental results and understanding dark matter distribution.

Purpose of the Study:

• To summarize progress in estimating the local dark matter density (ρDM,⊙).
• To compare common estimation methods and recent findings, particularly those utilizing ESA/Gaia data.
• To discuss the impact of galactic disequilibrium and baryon distribution uncertainties on ρDM,⊙ measurements.

Main Methods:

• Comparison of common methods for estimating local dark matter density.
• Analysis of recent studies, incorporating data from the ESA/Gaia satellite.
• Review of evidence for local disequilibrium and broken symmetries in the Milky Way.

Main Results:

• Local analyses suggest ρDM,⊙ in the range of 0.4-0.6 GeV/cm³.
• Global studies favor a slightly lower range of 0.3-0.5 GeV/cm³.
• Growing evidence indicates the Milky Way is not in a steady-state, impacting density estimations.

Conclusions:

• Precise ρDM,⊙ measurements require moving beyond idealized galaxy models.
• Understanding galactic disequilibrium and baryon distribution is critical for improving density estimates.
• Future constraints on ρDM,⊙ will benefit significantly from Gaia's final data release.