J/A+A/491/379 Velocities of galaxies in Abell 520 (Girardi+, 2008)
Cluster Abell 520: a perspective based on member galaxies.
A cluster forming at the crossing of three filaments?
Girardi M., Barrena R., Boschin W., Ellingson E.
<Astron. Astrophys., 491, 379-395 (2008)>
=2008A&A...491..379G 2008A&A...491..379G
ADC_Keywords: Clusters, galaxy ; Galaxies, photometry ; Radial velocities
Keywords: galaxies: clusters: individual: Abell 520 -
galaxies: clusters: general - galaxies: distances and redshifts
Abstract:
The connection of cluster mergers with the presence of extended,
diffuse radio sources in galaxy clusters is still debated. An
interesting case is the rich, merging cluster Abell 520, containing a
radio halo. A recent gravitational analysis has shown in this cluster
the presence of a massive dark core suggested to be a possible problem
for the current cold dark matter paradigm.
We aim to obtain new insights into the internal dynamics of Abell 520
analyzing velocities and positions of member galaxies.
Our analysis is based on redshift data for 293 galaxies in the cluster
field obtained combining new redshift data for 8 galaxies acquired at
the TNG with data obtained by CNOC team and other few data from the
literature. We also use new photometric data obtained at the INT
telescope. We combine galaxy velocities and positions to select 167
cluster members around z∼0.201. We analyze the cluster structure using
the weighted gap analysis, the KMM method, the Dressler-Shectman
statistics and the analysis of the velocity dispersion profiles. We
compare our results with those from X-ray, radio and gravitational
lensing analyses.
Description:
Multi-object spectroscopic observations of A520 were carried out at
the TNG telescope in December 2006. We used DOLORES/MOS with the
LR-B Grism 1.
As far as photometry is concerned, our observations were carried out
with the Wide Field Camera (WFC), mounted at the prime focus of the
2.5m INT telescope (located at Roque de los Muchachos observatory, La
Palma, Spain). We observed A520 in January 2008.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 49 293 Velocity catalog of 293 spectroscopically
measured galaxies in the field of A520
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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 --- [GBB2008] Sequential number
4 A1 --- n_[GBB2008] [*] * for non-cluster galaxies
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 r'mag ?=- r' SDSS magnitude
36- 41 I6 km/s cz Heliocentric radial velocity (cz☉)
43- 45 I3 km/s e_cz rms uncertainty on cz
47- 49 A3 --- r_cz [CPT+ ] Redshift source (1)
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Note (1): Source as follows:
C = CNOC, Canadian Network for Observational Cosmology,
Carlberg et al. (1996ApJ...462...32C 1996ApJ...462...32C),
Yee et al. (1996ApJS..102..269Y 1996ApJS..102..269Y)
P = Proust et al. (2000A&A...355..443P 2000A&A...355..443P)
T = TNG, this paper
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 26-Jan-2009