The dark matter profile of the milky way: A non-parametric reconstruction

Astrophysical Journal Letters 803.1 (2015) L3 reproduced by permission of the AASWe present the results of a new, non-parametric method to reconstruct the Galactic dark matter profile directly from observations. Using the latest kinematic data to track the total gravitational potential and the observed distribution of stars and gas to set the baryonic component, we infer the dark matter contribution to the circular velocity across the Galaxy. The radial derivative of this dynamical contribution is then estimated to extract the dark matter profile. The innovative feature of our approach is that it makes no assumption on the functional form or shape of the profile, thus allowing for a clean determination with no theoretical bias. We illustrate the power of the method by constraining the spherical dark matter profile between 2.5 and 25 kpc away from the Galactic center. The results show that the proposed method, free of widely used assumptions, can already be applied to pinpoint the dark matter distribution in the Milky Way with competitive accuracy, and paves the way for future developmentsF.I. acknowledges the support of the Spanish MINECO's "Centro de Excelencia Severo Ochoa" Programme under grant SEV-2012-0249 and the Consolider-Ingenio 2010 Programme under grant MultiDarkCSD2009-00064. Part of this work has been carried out during the workshop "What is the Dark Matter?" at NORDITA, Stockhol