J/MNRAS/456/2829 Radial velocities of galaxies in A523 field (Girardi+, 2016)
A multiwavelength view of the galaxy cluster Abell 523 and its peculiar diffuse
radio source.
Girardi M., Boschin W., Gastaldello F., Giovannini G., Govoni F.,
Murgia M., Barrena R., Ettori S., Trasatti M., Vacca V.
<Mon. Not. R. Astron. Soc., 456, 2829-2847 (2016)>
=2016MNRAS.456.2829G 2016MNRAS.456.2829G (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Radial velocities
Keywords: galaxies: clusters: general -
galaxies: clusters: individual: Abell 523 -
galaxies: kinematics and dynamics - radio continuum: general -
X-rays: galaxies: clusters
Abstract:
We study the structure of the galaxy cluster Abell 523 (A523) at
z=0.104 using new spectroscopic data for 132 galaxies acquired at the
Telescopio Nazionale Galileo, new photometric data from the Isaac
Newton Telescope, and X-ray and radio data from the Chandra and Very
Large Array archives. We estimate the velocity dispersion of the
galaxy population, σV=949-60+80km/s, and the X-ray
temperature of the hot intracluster medium, kT=5.3±0.3keV. We infer
that A523 is a massive system: M200∼7-9x1014M☉. The analysis
of the optical data confirms the presence of two subclusters, 0.75Mpc
apart, tracing the SSW-NNE direction and dominated by the two
brightest cluster galaxies (BCG1 and BCG2). The X-ray surface
brightness is strongly elongated towards the NNE direction, and its
peak is clearly offset from both the brightest cluster galaxies
(BCGs). We confirm the presence of a 1.3Mpc large radio halo,
elongated in the ESE-WNW direction and perpendicular to the
optical/X-ray elongation. We detect a significant radio/X-ray offset
and radio polarization, two features which might be the result of a
magnetic field energy spread on large spatial scales. A523 is found
consistent with most scaling relations followed by clusters hosting
radio haloes, but quite peculiar in the Pradio-LX relation: it is
underluminous in the X-rays or overluminous in radio. A523 can be
described as a binary head-on merger caught after a collision along
the SSW-NNE direction. However, minor optical and radio features
suggest a more complex cluster structure, with A523 forming at the
crossing of two filaments along the SSW-NNE and ESE-WNW directions.
Description:
Multi-object spectroscopic observations of A523 were carried out at
the TNG in 2012 December and 2014 January. We used the instrument
DOLORES in MOS mode with the LR-B Grism. In summary, we observed six
MOS masks for a total of 210 slits. The total exposure time was 3600s
for three masks, 5400s for two masks and 7200s for the last one.
Our photometric observations were carried out with the Wide Field
Camera (WFC), mounted at the prime focus of the 2.5-m INT telescope.
We observed A523 in g, r and i Sloan-Gunn filters in photometric
conditions and a seeing of ∼1.4arcsec.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 45 132 Radial velocities of 132 galaxies in the
field of A523
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- ID Sequential number
4 A1 --- n_ID [*AB] Note on ID (1)
6- 7 I2 h RAh Right ascension (J2000)
9- 10 I2 min RAm Right ascension (J2000)
12- 16 F5.2 s RAs Right ascension (J2000)
18 A1 --- DE- Declination sign (J2000)
19- 20 I2 deg DEd Declination (J2000)
22- 23 I2 arcmin DEm Declination (J2000)
25- 28 F4.1 arcsec DEs Declination (J2000)
30- 34 F5.2 mag rmag ?=- INT dereddened r-band magnitude
36- 41 I6 km/s HRV Heliocentric radial velocity
43- 45 I3 km/s e_HRV rms uncertainty on HRV
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Note (1): Notes as follows:
* = non-member galaxies
A = Galaxy ID 75 is the BCG1
B = Galaxy ID 56 is the BCG2
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 27-Sep-2016