Galaxy evolution in compact groups I: Revealing a transitional galaxy population through a multiwavelength approach

Abstract

Compact groups of galaxies (CGs) show members with morphological disturbances, mainly products of galaxy-galaxy interactions, thus making them ideal systems to study galaxy evolution, in high-density environment. To understand how this environment affects the properties of galaxies, we select a sample of 340 CGs in the Stripe 82 region, for a total of 1083 galaxies, and a sample of 2281 field galaxies as a control sample. By performing a multi-wavelength morphological fitting process using S-PLUS data, we divide our sample into early-type (ETG), late-type (LTG), and transition galaxies using the r-band Sérsic index and the colour (u-r). We find a bimodal distribution in the plane of the effective radius-Sérsic index, where a secondary "peculiar" galaxy population of smaller and more compact galaxies is found in CGs, which is not observed in the control sample. This indicates that galaxies are undergoing a morphological transformation in CGs. In addition, we find significant statistical differences in the distribution of specific Star Formation Rate (sSFR) when we compare both environments for LTGs and ETGs. We also find a higher fraction of quenched galaxies and a lower median sSFR in CGs than in the control sample, suggesting the existence of environmental effects favoring the cessation of star formation, regardless of galaxy type. Our results support the notion that CGs promote morphological and physical transformations, highlighting their potential as ideal systems for galaxy pre-processing.

17 pages, 15 figures. Accepted for publication in MNRAS

References in corpus (19)

• Galaxy Groups in the SDSS DR4: I. The Catalogue and Basic Properties
• The Importance of Satellite Quenching for the Build-Up of the Red Sequence of Present Day Galaxies
• LoCuSS: The slow quenching of star formation in cluster galaxies and the need for pre-processing
• Dependence of Galaxy Quenching on Halo Mass and Distance from its Centre
• Dissipation and Extra Light in Galactic Nuclei: III. 'Core' Ellipticals and 'Missing' Light
• Galaxy And Mass Assembly (GAMA): the wavelength-dependent sizes and profiles of galaxies revealed by MegaMorph
• Galaxy Colour, Morphology, and Environment in the Sloan Digital Sky Survey
• The Infrared Properties of Hickson Compact Groups
• The stripping of a galaxy group diving into the massive cluster A2142
• LoCuSS: Pre-processing in galaxy groups falling into massive galaxy clusters at z=0.2
• Evidence for tidal interaction and merger as the origin of galaxy morphology evolution in compact groups
• An environmental dependence of the physical and structural properties in the Hydra Cluster galaxies
• MegaMorph: classifying galaxy morphology using multi-wavelength Sérsic profile fits
• The Revealing Dust: Mid-Infrared Activity in Hickson Compact Group Galaxy Nuclei
• Quantified diffuse light in compact groups of galaxies
• The miniJPAS survey: The role of group environment in quenching the star formation
• The First Fall is the Hardest: The Importance of Peculiar Galaxy Dynamics at Infall Time for Tidal Stripping Acting at the Centers of Groups and Clusters
• Star Formation Enhancement in Barred Disk Galaxies in Interacting Galaxy Clusters
• CO in Hickson Compact Group galaxies with enhanced warm \htwo\ emission: Evidence for galaxy evolution?