Catalog of Isolated Galaxies Selected from the 2MASS Survey

TL;DR

This paper presents a comprehensive catalog of 3227 isolated galaxies identified from the 2MASS survey, providing a valuable resource for studying galaxy evolution in low-density environments.

Contribution

It introduces a new catalog of isolated galaxies based on the 2MASS survey using a modified isolation criterion, covering the entire sky with a large, well-defined sample.

Findings

Catalog contains 3227 isolated galaxies with Ks < 12 mag.

Includes 2493 very isolated galaxies for environmental studies.

Provides a uniform, all-sky sample suitable for evolutionary research.

Abstract

We search for isolated galaxies based on the automatic identification of isolated sources from the Two Micron All-Sky Survey (2MASS) followed by a visual inspection of their surroundings. We use the modified Karachentseva criterion to compile a catalog of 3227 isolated galaxies (2MIG), which contains 6% of 2MASS Extended Sources Catalog (or 2MASX) sources brighter than Ks = 12 mag with angular diameters a_K > 30 arcsec. The catalog covers the entire sky and has an effective depth of z = 0.02. The 2493 very isolated objects of the catalog, which we include into the 2MVIG catalog, can be used as a reference sample to investigate the effects of the environment on the structure and evolution of galaxies located in regions with extremely low density of matter.