Color Dependence in the Spatial Distribution of Satellite Galaxies

TL;DR

This study investigates how the color of satellite galaxies influences their spatial distribution around isolated galaxies, revealing differences in interloper contamination and radial profiles between red and blue satellites.

Contribution

It provides the first detailed analysis of color-dependent radial profiles of satellite galaxies using SDSS data, accounting for interloper contamination.

Findings

Blue satellites have shallower radial profiles than red satellites.

Red and blue primaries show different interloper fractions.

Interloper correction aligns the radial profile slopes for red and blue satellites.

Abstract

We explore the color dependence of the radial profile of satellite galaxies around isolated parent galaxies. Samples of potential satellites selected from large galaxy redshift surveys are significantly contaminated by interlopers -- objects not bound to the parent galaxy. We use the Sloan Digital Sky Survey to estimate the interloper fraction in samples of candidate satellite galaxies. We show that samples of red and blue satellites have different interloper populations: a larger fraction of blue galaxies are likely to be interlopers compared to red galaxies. Both with and without interloper subtraction, the radial profile of blue satellites is significantly shallower than that of red satellites. In addition, while red and blue primaries have different interloper fractions, the slope of the corrected radial profiles are consistent after interloper correction. We discuss the implications of these results for galaxy formation models.