Examinando por Autor "Beyoro Amado, Z."

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A morphological study of galaxies in ZwCl0024+1652, a galaxy cluster at redshift z ∼ 0.4
(Oxford Academics: Oxford University Press, 2019-02-11) Beyoro Amado, Z.; Povic, M.; Sánchez Portal, M.; Tessema, S. B.; Bongiovanni, Á.; Cepa, J.; Cerviño, M.; González Serrano, J. I.; Nadolny, J.; Pérez García, A. M.; Pérez Martínez, R.; Pintos Castro, I.; Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); Bongiovanni, Á. [0000-0002-3557-3234]; Povic, M. [0000-0002-9766-6110]; Pérez García, A. M. [0000-0003-1634-3588]; Pérez Martínez, R. [0000-0002-9127-5522]; Pintos Castro, I. [0000-0002-9133-4457]; Centros de Excelencia Severo Ochoa, INSTITUTO DE ASTROFISICA DE ANDALUCIA (IAA), SEV-2017-0709; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
The well-known cluster of galaxies ZwCl0024+1652 at z ∼ 0.4 lacks an in-depth morphological classification of its central region. While previous studies provide a visual classification of a patched area, we used the public code called galaxy Support Vector Machine (GALSVM) and HST/ACS data as well as the WFP2 master catalogue to automatically classify all cluster members up to 1 Mpc. GALSVM analyses galaxy morphologies through support vector machine (SVM). From the 231 cluster galaxies, we classified 97 as early types (ETs) and 83 as late types (LTs). The remaining 51 stayed unclassified (or undecided). By cross-matching our results with the existing visual classification, we found an agreement of 81 per cent. In addition to previous Zwcl0024 morphological classifications, 121 of our galaxies were classified for the first time in this work. In addition, we tested the location of classified galaxies on the standard morphological diagrams, colour–colour and colour–magnitude diagrams. Out of all cluster members, ∼20 per cent are emission-line galaxies, taking into account previous GLACE results. We have verified that the ET fraction is slightly higher near the cluster core and decreases with the clustercentric distance, while the opposite trend has been observed for LT galaxies. We found a higher fraction of ETs (54 per cent) than LTs (46 per cent) throughout the analysed central region, as expected. In addition, we analysed the correlation between the five morphological parameters (Abraham concentration, Bershady–Concelice concentration, asymmetry, Gini, and M20 moment of light) and the clustercentric distance, without finding a clear trend. Finally, as a result of our work, the morphological catalogue of 231 galaxies containing all the measured parameters and the final classification is available in the electronic form of this paper.
Restringido
GLACE survey: Galaxy activity in ZwCl0024+1652 cluster from strong optical emission lines
(Oxford Academics: Oxford University Press, 2021-01-16) Beyoro Amado, Z.; Sánchez Portal, M.; Bongiovanni, Á.; Povic, M.; Tessema, S. B.; Pérez Martínez, R.; Pérez García, A. M.; Cerviño, M.; Nadolny, J.; Cepa, J.; González Serrano, J. I.; Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); Ethiopian Space Science and Technology Institute (ESSTI); Centros de Excelencia Severo Ochoa, INSTITUTO DE ASTROFISICA DE ANDALUCIA (IAA), SEV-2017-0709; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Although ZwCl0024+1652 galaxy cluster at z ∼ 0.4 has been thoroughly analysed, it lacks a comprehensive study of star formation and nuclear activity of its members. With GaLAxy Cluster Evolution (GLACE) survey, a total of 174 Hα emissionline galaxies (ELGs) were detected, most of them having [N II]. We reduced and analysed a set of [O III] andHβ tunable filter (TF) observations within GLACE survey. Using Hα priors, we identified [O III] and Hβ in 35 (∼20 per cent) and 59 (∼34 per cent) sources, respectively, with 21 of them having both emission lines, and 20 having in addition [NII]. Applying BPT-NII diagnostic diagram, we classified these ELGs into 40 per cent star-forming (SF), 55 per cent composites, and 5 per cent LINERs. Star formation rate (SFR) measured through extinction corrected Hα fluxes increases with stellar mass (M∗), attaining its peak at M∗ ∼ 109.8M⊙. We observed that the cluster centre to ∼1.3Mpc is devoid of SF galaxies and AGN. Our results suggest that the star formation efficiency declines as the local density increases in the cluster medium. Moreover, the SF and AGN fractions drop sharply towards high-density environments. We observed a strong decline in SF fraction in high M., confirming that star formation is highly suppressed in high-mass cluster galaxies. Finally, we determined that SFR correlates with M. while specific SFR (sSFR) anticorrelates with M., both for cluster and field. This work shows the importance and strength of TF observations when studying ELGs in clusters at higher redshifts. We provide with this paper a catalogue of ELGs with Hβ and/or [O III] lines in ZwCl0024+1652 cluster.