Testing gravity with the Milky Way: Yukawa potential
Jakob Henrichs, M Lembo, Fabio Iocco, Luca Amendola
Abstract
We test a Yukawa correction to the Newtonian potential, making use of our own Galaxy---the Milky Way---as a test bed. We include as free parameter the Yukawa strength and range and the dark matter profile parameters, and compare several morphologies for the bulge, gas, and disk components, using Bayesian model selection criteria. We employ up-to-date datasets for both the visible (baryonic) component of the Milky Way, and for the tracers of the gravitational potential (the rotation curve). We find that the data are consistent with the Newtonian potential, and constrain the Yukawa coupling $\ensuremath{\beta}$ to be negative and $\ensuremath{\lambda}$ to range along the curve $\ensuremath{\lambda}=a|\ensuremath{\beta}{|}^{c}$ with $a=(0.77\ifmmode\pm\else\textpm\fi{}0.06)\text{ }\text{ }\mathrm{kpc}$ and $c=\ensuremath{-}0.50{3}_{\ensuremath{-}0.019}^{+0.016}$.