Revisiting the low-luminosity galaxy population of the NGC 5846 group with SDSS

TL;DR

This study analyzes the properties of low-luminosity galaxies in the NGC 5846 group, revealing their photometric and spectroscopic characteristics and how they relate to environment and galaxy evolution.

Contribution

It provides a detailed analysis of low-luminosity galaxy populations in NGC 5846 using SDSS data, focusing on their photometric and spectroscopic properties and environmental dependence.

Findings

Photometric scaling relations for early-type dwarfs established

Morphology distribution depends on environment

Star formation and metallicity characteristics of emission-line galaxies analyzed

Abstract

Low-luminosity galaxies are known to outnumber the bright galaxy population in poor groups and clusters of galaxies. Yet, the investigation of low-luminosity galaxy populations outside the Local Group remains rare and the dependence on different group environments is still poorly understood. Previous investigations revealed photometric scaling relations for early-type dwarfs and a strong dependence of morphology with environment. The present study aims to analyse the photometric and spectroscopic properties of the low-luminosity galaxy population in the nearby, well-evolved and early-type dominated NGC 5846 group of galaxies. It is the third most massive aggregate of early-type galaxies after the Virgo and Fornax clusters in the local universe. Photometric scaling relations and the distribution of morphological types as well as the characteristics of emission-line galaxies are investigated. Spectroscopically selected low-luminosity group members from the Sloan Digital Sky Survey with cz<3000 km/s within a radius of 2 deg=0.91 Mpc around NGC 5846 are analysed. Surface brightness profiles of early-type galaxies are fit by a Sersic model r^(1/n). Star formation rates, oxygen abundances and emission characteristics are determined for emission-line galaxies. [abridged]