Evidence for dark matter in the inner Milky Way

Abstract

The ubiquitous presence of dark matter in the universe is today a central tenet in modern cosmology and astrophysics. Ranging from the smallest galaxies to the observable universe, the evidence for dark matter is compelling in dwarfs, spiral galaxies, galaxy clusters as well as at cosmological scales. However, it has been historically difficult to pin down the dark matter contribution to the total mass density in the Milky Way, particularly in the innermost regions of the Galaxy and in the solar neighbourhood. Here we present an up-to-date compilation of Milky Way rotation curve measurements, and compare it with state-of-the-art baryonic mass distribution models. We show that current data strongly disfavour baryons as the sole contribution to the galactic mass budget, even inside the solar circle. Our findings demonstrate the existence of dark matter in the inner Galaxy while making no assumptions on its distribution. We anticipate that this result will compel new model-independent constraints on the dark matter local density and profile, thus reducing uncertainties on direct and indirect dark matter searches, and will shed new light on the structure and evolution of the Galaxy.

First submitted version of letter published in Nature Physics on Febuary 9, 2015: http://www.nature.com/nphys/journal/vaop/ncurrent/full/nphys3237.html

References in corpus (7)

• Trigonometric Parallaxes of Massive Star Forming Regions: VI. Galactic Structure, Fundamental Parameters and Non-Circular Motions
• The Local Dark Matter Density
• Galactic masers and the Milky Way circular velocity
• Milky Way Kinematics: Measurements at the Subcentral Point of the Fourth Quadrant
• The Long Bar in the Milky Way. Corroboration of an old hypothesis
• Open Clusters as Galactic Disk Tracers: I. Project Motivation, Cluster Membership and Bulk Three-Dimensional Kinematics
• The current best estimate of the Galactocentric distance of the Sun based on comparison of different statistical techniques

Cited by in corpus (13)

• Dark matter spikes in the vicinity of Kerr black holes
• Signatures of Majorana dark matter with t-channel mediators
• Sensitivity of the Cherenkov Telescope Array to the detection of a dark matter signal in comparison to direct detection and collider experiments
• Dark Matter in $\gamma$ lines: Galactic Center vs dwarf galaxies
• The dark matter profile of the Milky Way: a non-parametric reconstruction
• $\text{galkin}$: a new compilation of the Milky Way rotation curve data
• Testing the weak equivalence principle by differential measurements of fundamental constants in the Magellanic Clouds
• On the Role of Neutrinos Telescopes in the Search for Dark Matter Annihilations in the Sun
• Stellar convective cores as dark matter probes
• Modelling mass distribution of the Milky Way galaxy using Gaia billion-star map
• Solar System constraints on Renormalization Group extended General Relativity: The PPN and Laplace-Runge-Lenz analyses with the external potential effect
• The Density of Dark Matter in the Galactic Bulge and Implications for Indirect Detection
• Does the gamma-ray signal from the central Milky Way indicate Sommerfeld enhancement of dark matter annihilation?