Environmental Dependence of Galaxy properties: A study of 341 Ring Galaxies in Cosmic Voids

TL;DR

This study analyzes 341 ring galaxies in cosmic voids, revealing their morphology, distribution, and evolution, and highlighting their distinct properties influenced by the low-density environment.

Contribution

It provides the first detailed analysis of void ring galaxies, showing their morphology, distribution, and environmental dependence, emphasizing secular evolution in low-density regions.

Findings

91.5% of ring galaxies are located away from void cores.

Outer pseudorings are most common at 56.3%.

Ring galaxies are more massive, redder, and have lower star formation rates than the general void population.

Abstract

We investigate the morphological and physical properties of ring galaxies residing within cosmic voids. Using void catalogs from VoidFinder, ring candidates identified via the Galaxy Zoo 2 decision tree, and morphological classifications from the Buta (2017) CVRHS based catalog, we analyze a sample of 341 void ring galaxies and find a radial preference, with 91.5% located away from the void cores. Morphologically, inner rings and inner pseudorings account for 45.2% of the sample while outer pseudorings are even more common(56.3%) and outer rings appear in 17.9% of galaxies, which points to secular evolution driven by internal dynamics as the primary formation mechanism. Compared to the general void population, our sample ring galaxies are found to be more massive, redder, and have lower specific star formation rates. Subtle gradients in stellar mass and sSFR from void centers to edges also shows a gentle, density-dependent evolutionary progression. Our results show ring galaxies as a distinct, secularly evolved population shaped by the weakest large-scale environmental gradients