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This article discusses the problems of the physical properties of globular clusters in galaxy clusters and groups. Observational data of globular clusters in galaxy clusters and individual groups were analyzed. Based on the catalog of globular cluster systems, an analysis was performed to find statistical patterns between their main characteristics and the parent galaxy. It was found that 98 globular cluster systems are located in groups, and 258 in galaxy clusters. The remaining 85 systems are still difficult to attribute – whether they belong to clusters or groups of galaxies. It is shown that among the galaxy groups, the Local Group occupies a special place, and the NGC 5128 group is in second place. Of the members of the Local Group, 11 galaxies contain globular cluster systems, 5 of which are in the Milky Way subgroup, and the rest attributed to the M31 subgroup. The total number of observed globular clusters in the Local Group is 724±103. Among the galaxy clusters containing globular cluster systems, the Virgo cluster ranks first, followed by Fornax and Coma Berenices. 142 globular cluster systems have been found in the Virgo cluster, of which 92 systems are elliptical galaxies. It has been shown that the elliptical galaxies of the Virgo cluster contain almost twice as many globular cluster systems, and the average number of clusters in the system is analogous. In the Fornax clusters, the total number of globular cluster systems found is 55, and in the Coma cluster, 20 systems around elliptical and lenticular galaxies have been found. Also, for two galaxy clusters, a logarithmic relationship was found between the number of globular clusters in a system and the absolute magnitude of the host galaxy

An accurate mass calibration of galaxy clusters is a crucial step towards precise constraints on the cosmological parameters σ 8 and Ω m from clusters. Cluster masses can be estimated assuming hydrostatic equilibrium, but several physical and observational effects can alter this calculation. One of those are projection effects which are the focus of our present analysis. We present a case study of the simulated Virgo cluster, extracted from the CLONE constrained simulation. We study Virgo pressure and electron density quantities projected along different directions, including along the Milky Way-Virgo axis which mimics our observation direction. We show two main projection effects: the role of the integrated mass along the line of sight (LoS) in each chosen direction, including the presence of massive objects, and the signature of small scale physics in the core of the cluster along these directions.

The goal of this work is to use observed galaxy surface brightness profiles at high redshifts to determine, among a few candidates, the cosmological model best suited to interpret these observations. Theoretical predictions of galactic surface brightness profiles are compared to observational data in two cosmological models, ΛCDM and Einstein-de Sitter, to calculate the evolutionary effects of different spacetime geometries in these profiles in order to try to find out if the available data is capable of indicating the cosmology that most adequately represents actual galactic brightness profiles observations. Starting from the connection between the angular diameter distance and the galactic surface brightness as advanced by Ellis and Perry (Mon. Not. R. Astron. Soc. 187:357, 1979), we derived scaling relations using data from the Virgo galactic cluster in order to obtain theoretical predictions of the galactic surface brightness modeled by the Sérsic profile at redshift values equal to a sample of galaxies in the range 1.5≲z≲2.3 composed by a subset of Szomoru’s et al. (Astrophys. J. 749:121, 2012) observations. We then calculated the difference between theory and observation in order to determine the changes required in the effective radius and effective surface brightness so that the observed galaxies may evolve to have features similar to the Virgo cluster ones. Our results show that within the data uncertainties of this particular subset of galaxies it is not possible to distinguish which of the two cosmological models used here predicts theoretical curves in better agreement with the observed ones, that is, one cannot identify a clear and detectable difference in galactic evolution incurred by the galaxies of our sample when applying each cosmology. We also concluded that the Sérsic index n does not seem to play a significant effect in the evolution of these galaxies. Further developments of the methodology employed here to test cosmological models are also discussed.

In a growing number of galaxy clusters diffuse extended radio sources have been found. These sources are not directly associated with individual cluster galaxies. The radio emission reveal the presence of cosmic rays and magnetic fields in the intracluster medium (ICM). We classify diffuse cluster radio sources into radio halos, cluster radio shocks (relics), and revived AGN fossil plasma sources. Radio halo sources can be further divided into giant halos, mini-halos, and possible “intermediate” sources. Halos are generally positioned at cluster center and their brightness approximately follows the distribution of the thermal ICM. Cluster radio shocks (relics) are polarized sources mostly found in the cluster’s periphery. They trace merger induced shock waves. Revived fossil plasma sources are characterized by their radio steep-spectra and often irregular morphologies. In this review we give an overview of the properties of diffuse cluster radio sources, with an emphasis on recent observational results. We discuss the resulting implications for the underlying physical acceleration processes that operate in the ICM, the role of relativistic fossil plasma, and the properties of ICM shocks and magnetic fields. We also compile an updated list of diffuse cluster radio sources which will be available on-line ( http://galaxyclusters.com ). We end this review with a discussion on the detection of diffuse radio emission from the cosmic web.

Supermassive black holes (SMBHs) play[-105pt]Kindly check and confirm the Article Title. fundamental roles in the evolution of galaxies, groups, and clusters. The fossil record of supermassive black hole outbursts is seen through the cavities and shocks that are imprinted on these gas-rich systems. For M87, the central galaxy in the Virgo cluster, deep Chandra observations illustrate the physics of AGN feedback in hot, gas-rich atmospheres and allow measurements of the age, duration, and power of the outburst from the supermassive black hole in M87 that produced the observed cavities and shocks in the hot X-ray atmosphere.

The presence of Gaia DR3 data allows us to conduct more comprehensive research about the large population of open clusters in the Galaxy. Investigating the effects of the Galactic environment on open clusters will provide some insights regarding their evolution driven by external factors. Observing the clusters’ shapes and movements is genuinely essential since they represent the physical conditions under their relationship with the Galactic environment. By harnessing the latest and most complete stellar data, we measure the influence of the Galactic environment on a large population of open clusters enclosing an area of 1 kpc in radius through the clusters’ compression in velocity and dispersion spaces. In this study, we observed that open clusters are compressed to the Galactic plane direction, both in velocity and dispersion spaces.

I summarize the scenario by Goudfrooij (2018) in which the bulk of the ultraviolet (UV) upturn of giant early-type galaxies (ETGs) is due to helium-rich stellar populations that formed in massive metal-rich globular clusters (GCs) and subsequently dissolved in the strong tidal field in the central regions of the massive host galaxy. These massive GCs are assumed to show UV upturns similar to those observed recently in M87, the central galaxy in the Virgo cluster of galaxies. Data taken from the literature reveals a strong correlation between the strength of the UV upturn and the specific frequency of metal-rich GCs in ETGs. Adopting a Schechter function parametrization of GC mass functions, simulations of long-term dynamical evolution of GC systems show that this correlation can be explained by variations in the characteristic truncation mass M c such that M c increases with ETG luminosity in a way that is consistent with observed GC luminosity functions in ETGs. These findings suggest that the nature of the UV upturn in ETGs and the variation of its strength among ETGs are causally related to that of helium-rich populations in massive GCs, rather than intrinsic properties of field stars in ETGs.

Cosmological simulations predict that the Universe contains a network of intergalactic gas filaments, within which galaxies form and evolve. However, the faintness of any emission from these filaments has limited tests of this prediction. We report the detection of rest-frame ultraviolet Lyman-α radiation from multiple filaments extending more than one megaparsec between galaxies within the SSA22 protocluster at a redshift of 3.1. Intense star formation and supermassive black-hole activity is occurring within the galaxies embedded in these structures, which are the likely sources of the elevated ionizing radiation powering the observed Lyman-α emission. Our observations map the gas in filamentary structures of the type thought to fuel the growth of galaxies and black holes in massive protoclusters.

We present surface photometry and stellar kinematics of NGC 4264, a lenticular galaxy in the region of the Virgo Cluster undergoing a tidal interaction with its neighbour, NGC 4261. We measured the bar radius and strength from SDSS imaging and the bar pattern speed from MUSE integral-field spectroscopy. We find that NGC 4264 hosts a strong and large bar, which is rotating fast. The accurate measurement of the bar rotation rate allows us to exclude that the formation of the bar was triggered by the ongoing interaction.