More Local Volume dwarf galaxy candidates

TL;DR

This paper reports the discovery of 40 new dwarf galaxy candidates in the Local Volume using DESI Legacy Imaging Surveys, including their potential group memberships and mass estimates, enhancing understanding of local galaxy populations.

Contribution

It introduces a new search for dwarf galaxy candidates in the Local Volume, identifying 40 candidates and providing mass estimates for associated galaxy groups.

Findings

40 dwarf galaxy candidates identified in the Local Volume.

Mass of the NGC6744 group estimated at approximately 1.88×10^12 solar masses.

Distribution and morphological segregation of galaxies around the Sombrero galaxy observed.

Abstract

We present the results of searching for new dwarf galaxies in the Local Volume. We found 40 satellite candidates in the double-virial-radius regions of 20 Milky Way-like and LMC-like galaxies in the southern sky using DESI Legacy Imaging Surveys, 10 of which were known but not clearly associated with the Local Volume previously. Among the 40 satellite candidates, 8 are supposed members of the NGC6744 group and 13 are located in the vicinity of the Sombrero galaxy. Based on seven companions to the giant spiral galaxy NGC\,6744 with measured radial velocities, we estimate that the total mass of the group is $M_T = (1.88\pm0.71)\times 10^{12} M_{\odot}$ and the total mass-to-K-luminosity ratio $M_T/L_K = (16.1\pm6.0) M_{\odot}/L_{\odot}$. We reproduce a distribution of 68 early- and late-type galaxies in the Local Volume situated around the Sombrero, noting their strong morphological segregation and also the presence of a foreground diffuse association of dwarf galaxies at 8 degrees to SE from the Sombrero.