Galaxy evolution studies in clusters: the case of Cl0024 + 1652 cluster galaxies at z ∼ 0.4

Abstract

Studying the transformation of cluster galaxies contributes a lot to have a clear picture of evolution of the universe. Towards that we are studying different properties (morphology, star formation, AGN contribution and metallicity) of galaxies in clusters up to z ∼ 1.0 taking three different clusters: ZwCl0024 + 1652 at z ∼ 0.4, RXJ1257 + 4738 at z ∼ 0.9 and Virgo at z ∼ 0.0038. For ZwCl0024 + 1652 and RXJ1257 + 4738 clusters we used tunable filters data from GLACE survey taken with GTC 10.4 m telescope and other public data, while for Virgo we used public data. We did the morphological classification of 180 galaxies in ZwCl0024 + 1652 using galSVM, where 54 % and 46 % of galaxies were classified as early-type (ET) and late-type (LT) respectively. We did a comparison between the three clusters within the clustercentric distance of 1 Mpc and found that ET proportion (decreasing with redshift) dominates over the LT (increasing with redshift) throughout. We finalized the data reduction for ZwCl0024 + 1652 cluster and identified 46 [OIII] and 73 Hβ emission lines. For this cluster we have classified 22 emission line galaxies (ELGs) using BPT-NII diagnostic diagram resulting with 14 composite, 1 AGN and 7 star forming (SF) galaxies. We are using these results, together with the public data, for further analysis of the variations of properties in relation to redshift within z < 1.0.

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

“…The Spearman's rank correlation coefficients show that the correlation between galaxies' properties and their environments are weaker compared to those of more relaxed clusters. Nonetheless, they seem to follow the same direction as indicated by general evolution of bound large scale structure such as clusters (see, e.g., [6]). The Dressler's morphology-density relation in our work is in the range of 0.209 -0.346, comparable to the range of 0.271 -0.96 found by Houghton ([17]).…”

Galaxy evolution studies in clusters: the case of Cl0024+1652 cluster galaxies at z$\sim$0.4

“…The classification is in ∼ 80% agreement with previous works (Moran et al 2007) and 121 new galaxies have been classified. With this work we obtained one of the most complete morphological catalogue of ZwCl0024 + 1652 cluster within the clustercentric radius of 1 Mpc (Beyoro-Amado et al 2019).…”

“…Research results show that significant evolution in properties of galaxies within clusters are observed as a function of redshift. According to previous studies, the cores of low redshift clusters are dominated by red ET galaxies while the blue LT galaxy population dominates the higher redshift (z) clusters (e.g., Butcher & Oemler 1984, Beyoro-Amado et al 2019. Concerning the star formation activity, an increase of the obscured SF in mid-infrared (MIR) and far-infrared (FIR) surveys of distant clusters has been indicated (e.g., Haines et al 2009).…”

“…Morphological classification of galaxies could be performed either by traditional (visual inspection; e.g., Lintott et al 2011) or modern techniques. The modern techniques can be either parametric, performed by fitting some parameters assuming a predefined parametric model (e.g., Tarsitano et al 2018), or non parametric, where no specific analytic model is assumed while performed by measuring a set of well-chosen observables (e.g., Pović et al 2015, Huertas-Company et al 2015, Pintos-Castro et al 2016, Beyoro-Amado et al 2019. Previous studies show that local density has effects on galaxy morphology (e.g., Nantais et al 2013); as well as SF activities (e.g., Woo et al 2013).…”

Development in astronomy in Ethiopia and East-Africa through nuclear activity in galaxies

“…Regarding ZwCl0024 cluster, emission line galaxies have been previously selected and analysed in H α and [NII] lines (Sánchez-Portal et al 2015). We carried out morphological classification of galaxies in ZwCl0024, in a consistent way as in RXJ1257, by classifying all galaxies as early-or late-types, and obtaining the most detailed catalogue AGN and development in astronomy in Ethiopia and East-Africa 5 up to date up to a clustercentric distance of 1 Mpc (Beyoro-Amado et al 2019). Data reduction and analysis of H β and [OIII] lines in the ZwCl0024 cluster has been finalised.…”