A distance of 13 Mpc resolves the claimed anomalies of the galaxy lacking dark matter

TL;DR

Reevaluating the distance to a diffuse galaxy suggests it is not dark matter deficient, aligning its properties with typical low surface brightness galaxies and resolving previous anomalies.

Contribution

The paper demonstrates that adjusting the galaxy's distance to 13 Mpc reconciles its properties with standard galaxy models, challenging prior claims of dark matter deficiency.

Findings

The galaxy's revised distance is 13 Mpc, not 20 Mpc.

At 13 Mpc, the galaxy has typical properties and substantial dark matter content.

Previous anomalies are resolved with the revised distance estimate.

Abstract

The claimed detection of a diffuse galaxy lacking dark matter represents a possible challenge to our understanding of the properties of these galaxies and galaxy formation in general. The galaxy, already identified in photographic plates taken in the summer of 1976 at the UK 48-in Schmidt telescope, presents normal distance-independent properties (e.g. colour, velocity dispersion of its globular clusters). However, distance-dependent quantities are at odds with those of other similar galaxies, namely the luminosity function and sizes of its globular clusters, mass-to-light ratio and dark matter content. Here we carry out a careful analysis of all extant data and show that they consistently indicate a much shorter distance (13 Mpc) than previously indicated (20 Mpc). With this revised distance, the galaxy appears to be a rather ordinary low surface brightness galaxy (R_e=1.4+-0.1 kpc; M*=6.0+-3.6x10^7 Msun) with plenty of room for dark matter (the fraction of dark matter inside the half mass radius is >75% and M_halo/M*>20) corresponding to a minimum halo mass >10^9 Msun. At 13 Mpc, the luminosity and structural properties of the globular clusters around the object are the same as those found in other galaxies.