Newtonian acceleration scales in spiral galaxies

TL;DR

This study analyzes the constancy of dark matter and baryonic acceleration scales in spiral galaxies, using MCMC methods on a large sample to assess their potential universality and dependence on galaxy properties.

Contribution

It provides a comprehensive catalog of acceleration measurements in spiral galaxies and critically examines the universality of these scales with statistical analysis.

Findings

Weak correlation between acceleration scales and virial mass

Results suggest acceleration scales are not strictly universal

Sample selection influences the observed relationships

Abstract

We revisit the issue of the constancy of the dark matter (DM) and baryonic Newtonian acceleration scales within the DM scale radius by considering a large sample of late - type galaxies. We rely on a Markov Chain Monte Carlo (MCMC) method to estimate the parameters of the halo model and the stellar mass - to - light ratio and then propagate the uncertainties from the rotation curve data to the estimate of the acceleration scales. This procedure allows us to compile a catalog of 58 objects with estimated values of the $B$ band absolute magnitude $M_B$, the virial mass $M_{vir}$, the DM and baryonic Newtonian accelerations (denoted as $g_{DM}(r_0)$ and $g_{bar}(r_0)$, respectively) within the scale radius $r_0$ which we use to investigate whether it is possible to define a universal acceleration scale. We find a weak but statistically meaningful correlation with $M_{vir}$ thus making us argue against the universality of the acceleration scales. However, the results somewhat depend on the sample adopted so that a careful analysis of selection effects should be carried out before any definitive conclusion can be drawn.