On The Origin And Evolution Of The Intra-Cluster Light: A Brief Review Of The Most Recent Developments

TL;DR

This review discusses the formation, evolution, and observational methods of intracluster light (ICL) in galaxy clusters, highlighting recent advances and its use as a dark matter tracer, integrating theoretical and observational perspectives.

Contribution

It provides a comprehensive overview of the mechanisms behind ICL formation, addresses definitional challenges, and reviews recent studies utilizing ICL as a dark matter tracer.

Findings

ICL formation mechanisms are diverse and complex.

Definitional issues hinder consistent comparisons across studies.

Recent work successfully uses ICL to trace dark matter distribution.

Abstract

Not all the light in galaxy groups and clusters comes from stars that are bound to galaxies. A significant fraction of it constitutes the so-called intracluster or diffuse light (ICL), a low surface brightness component of groups/clusters generally found in the surroundings of the brightest cluster galaxies and intermediate/massive satellites. In this review, I will describe the mechanisms responsible for its formation and evolution, considering the large contribution given to the topic in the last decades by both the theoretical and observational sides. Starting from the methods that are commonly used to isolate the ICL, I will address the remarkable problem given by its own definition, which still makes the comparisons among different studies not trivial, to conclude by giving an overview of the most recent works that take advantage of the ICL as a luminous tracer of the dark matter distribution in galaxy groups and clusters.