Testing gravity with the Milky Way: Yukawa potential

TL;DR

This study tests a Yukawa correction to gravity using the Milky Way's rotation curve and baryonic data, finding consistency with Newtonian gravity and constraining the Yukawa parameters.

Contribution

It introduces a comprehensive analysis of Yukawa gravity corrections in the Milky Way, including dark matter and baryonic components, using Bayesian model selection.

Findings

Data are consistent with Newtonian gravity.

Yukawa coupling $eta$ is constrained to be negative.

Yukawa range $ ext{lambda}$ follows a specific relation with $eta$.

Abstract

We test a Yukawa correction to the Newtonian potential, making use of our own Galaxy - the Milky Way - as a testbed. 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, also 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 $\beta$ to be negative and $\lambda$ to range along the curve $\lambda = a|\beta|^{c}$ with $a = (0.77 \pm 0.06)$ kpc and $c = -0.503\substack{+0.016 \\ -0.019}$.