Galaxy clusters form through nonlinear growth of primordial density fluctuations and are the most massive gravitationally-bound objects in the present Universe. Their number density at different epochs and their properties depend strongly on the properties of Dark Matter and Dark Energy, making clusters a powerful tool for observational cosmology. Observations of the hot gas filling the gravitational potential well of a cluster enable us to study gas-dynamical and plasma effects, and how the supermassive black holes affect heating and cooling of the gas on cluster scales. The work of Yakov Borisovich Zeldovich has had a profound impact on virtually all cosmological and astrophysical studies of galaxy clusters, introducing such concepts as the Harrison—Zeldovich spectrum, the Zeldovich approximation, baryon acoustic peaks, and the Sunyaev—Zeldovich effect. Here we review the most basic properties of clusters and their role in modern astrophysics and cosmology.

PACS: 97.60.Lf, 98.65.−r, 98.80.Bp (all) DOI: 10.3367/UFNe.0184.201404a.0339 URL: https://ufn.ru/en/articles/2014/4/b/ 000338713200001 2-s2.0-84903958352 2014PhyU...57..317V Citation: Vikhlinin A A, Kravtsov A V, Markevich M L, Sunyaev R A, Churazov E M "Clusters of galaxies" Phys. Usp. 57 317–341 (2014) BibTexBibNote ® (generic)BibNote ® (RIS)MedlineRefWorks Received: 19th, February 2014, accepted: 25th, February 2014 Оригинал: Вихлинин А А, Кравцов А В, Маркевич М Л, Сюняев Р А, Чуразов Е М «Скопления галактик» УФН 184 339–366 (2014); DOI: 10.3367/UFNr.0184.201404a.0339