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arXiv · 2106.14581

Properties of the Environment of Galaxies in Clusters of Galaxies CL 0024+1654 and RX J0152.7-1357

Premana W. Premadi·Dading H. Nugroho·Anton T. Jaelani
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Abstract

We report the results of combined analyses of X-ray and optical data of two galaxy clusters, CL 0024$+$1654 and RX J0152.7$-$1357 at redshift $z = 0.395$ and $z = 0.830$, respectively, which offer a holistic physical description of the two clusters. Our X-ray analysis yields temperature and density profile of the gas in the intra-cluster medium (ICM). Using optical photometric and spectroscopic data, complemented with mass distribution from gravitational lensing study, we investigate any possible correlation between the physical properties of the galaxy members, i.e., their color, morphology, and star formation rate (SFR) with their environments. We quantify the properties of the environment of each galaxy by galaxy number density, ICM temperature, and mass density. Although our result shows that the two clusters exhibit a weaker correlation compared to relaxed clusters, it still confirms the significant effect of the ICM on the SFRs in the galaxies. The closer relation between galaxy physical property and the condition of its immediate environment found in this work indicates the locality of galaxy evolution, even within a larger bound system such as cluster. Various physical mechanisms are suggested to explain the relation between the properties of galaxies and their environment.

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Premana W. Premadi, Dading H. Nugroho, Anton T. Jaelani. 2021-12-03. Properties of the Environment of Galaxies in Clusters of Galaxies CL 0024+1654 and RX J0152.7-1357. https://doi.org/10.5614/j.math.fund.sci.2021.53.3.7

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