Access to Astronomical Catalogues

← Click to display the menu
J/A+A/607/A131       Abell 520 galaxies redshifts                (Deshev+, 2017)

Galaxy evolution in merging clusters: The passive core of the "Train Wreck" cluster of galaxies, A520. Deshev B., Finoguenov A., Verdugo M., Ziegler B., Park C., Seong Hwang H., Haines C., Kamphuis P., Tamm A., Einasto M., Hwang N., Park B.-G. <Astron. Astrophys. 607, A131 (2017)> =2017A&A...607A.131D (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Galaxies, optical ; Galaxies, photometry ; Galaxies, spectra ; Galaxy catalogs ; Photometry, SDSS ; Redshifts ; Spectroscopy Keywords: galaxies: clusters: general - galaxies: clusters: individual: Abell 520 - galaxies: evolution Abstract: The mergers of galaxy clusters are the most energetic events in the universe after the Big Bang. An ever increasing fraction of local clusters exhibit signs of recent or past mergers. Our goal is to probe how these mergers affect the evolution and content of their member galaxies. We specifically aim to answer the following questions: Is the quenching of star formation in merging clusters enhanced when compared with relaxed clusters? Is the quenching accompanied by a (short lived) burst of star formation? We obtained optical spectroscopy of $>400$ galaxies in the field of the merging cluster Abell 520. We combine these observations with archival data to get a comprehensive picture of the state of star formation in the members of this merging cluster. Finally, we compare these observations with a control sample of 10 non-merging clusters at the same redshift from The Arizona Cluster Redshift Survey (ACReS). We split the member galaxies in passive, star forming or recently quenched depending on their spectra. The core of the merger shows a decreased fraction of star-forming galaxies compared to clusters in the non-merging sample. This region, dominated by passive galaxies, is extended along the axis of the merger. We find evidence of rapid quenching of the galaxies during the core passage with no signs of a star burst on the time scales of the merger. Additionally, we report the tentative discovery of an infalling group along the main filament feeding the merger, currently at ∼2.5Mpc from the merger centre. This group contains a high fraction of star forming galaxies as well as ∼2/3 of all the recently quenched galaxies in our survey. Description: Multi-fibre spectroscopy carried out with Hectospec on MMT, USA on 19 and 22 of February 2014. Grism 270 was used. Photometry with SExtractor on images from Megacam on CFHT in Hawaii, USA. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 56 407 Redshifts of 407 galaxies in the field of A520 spectra.fits 2880 4865 Spectra
Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 4 I4 --- Num Sequential number 6- 13 F8.5 deg RAdeg Right ascension (J2000) 15- 22 F8.5 deg DEdeg Declination (J2000) 24- 30 F7.5 --- z Redshift 32- 38 F7.5 --- e_z Uncertainty on redshift 40- 46 F7.3 mag rMAG Absolute r' SDSS magnitude 48- 54 F7.3 mag gMAG Absolute g' SDSS magnitude 56 I1 --- Memb [1/3] Membership (1)
Note (1): Membership code as follows: 1 = cluster member 2 = near field 3 = non member
Acknowledgements: Boris Deshev, boris(at)
(End) Patricia Vannier [CDS] 19-Jul-2017
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

catalogue service