J/AJ/123/2261 Radial velocities in A2256 (Berrington+, 2002)
The dynamics of the merging galaxy cluster system A2256:
evidence for a new subcluster.
Berrington R.C., Lugger P.M., Cohn H.N.
<Astron. J. 123, 2261 (2002)>
=2002AJ....123.2261B 2002AJ....123.2261B
ADC_Keywords: Clusters, galaxy ; Radial velocities
Keywords: galaxies: clusters: individual (A2256)
Abstract:
We present 236 new radial velocities of galaxies in the cluster A2256
measured with the WIYN Hydra Multi-Object Spectrograph. Combined with
the previous work of Fabricant, Kent, & Kurtz (1989ApJ...336...77F 1989ApJ...336...77F),
we have velocities for a total of 319 galaxies, of which 277 are
cluster members. In addition to the new radial velocities, we present
a 3x3 image mosaic in the R band of the central 19'x19' region of
A2256, from which we obtained photometry for 861 galaxies. These data
provide strong evidence for a merger event between two groups. In
addition, we present evidence for the presence of a third group, on
the outer reaches of the system, that is just now beginning to merge
with the system.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 64 319 Galaxy Catalog for A2256
table10.dat 42 34 Radio source positions in A2256
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See also:
J/ApJ/534/114 : RASSCALS: X-ray and optical study (Mahdavi+, 2000)
J/ApJS/129/435 : NORAS galaxy cluster survey. I. (Bohringer+, 2000)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- [BLC2002] Galaxy identification number
6- 7 I2 h RAh Hour of Right Ascension (J2000)
9- 10 I2 min RAm Minute of Right Ascension (J2000)
12- 15 F4.1 s RAs Second of Right Ascension (J2000)
16 A1 --- DE- Sign of Declination (J2000)
17- 18 I2 deg DEd Degree of Declination (J2000)
20- 21 I2 arcmin DEm Arcminute of Declination (J2000)
23- 26 F4.1 arcsec DEs Arcsecond of Declination (J2000)
28- 32 F5.2 mag Rcmag ? The Kron-Cousins R band magnitude as
reported by Faint-Object Classification
Analysis System
34- 37 F4.2 mag e_Rcmag ? The 1σ error in Rmag
39- 43 F5.2 mag rmag ? The Fabricant et al. (1989ApJ...336...77F 1989ApJ...336...77F)
r band isophotal magnitude
45- 52 F8.2 km/s cz The radial velocity (1)
54- 59 F6.2 km/s e_cz The 1σ error in cz
61- 63 I3 --- [FKK89] ? Fabricant et al. (1989ApJ...336...77F 1989ApJ...336...77F)
identification number
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Note (1): Obtained either in the present study or in the previous
studies of Faber & Dressler (1977AJ.....82..187F 1977AJ.....82..187F) and Fabricant et al.
(1989ApJ...336...77F 1989ApJ...336...77F). The new velocity measurement is reported for
those galaxies that were remeasured.
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Byte-by-byte Description of file: table10.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- Comp Radio Component, from
Roettiger et al. 1993ApJ...407L..53R 1993ApJ...407L..53R and
Bridle et al. 1979A&A....80..201B 1979A&A....80..201B
4- 5 I2 h RAh Right ascension (J2000)
7- 8 I2 min RAm Right ascension (J2000)
10- 13 F4.1 s RAs Right ascension (J2000)
15 A1 --- DE- Declination sign (J2000)
16- 17 I2 deg DEd Declination (J2000)
19- 20 I2 arcmin DEm Declination (J2000)
22- 25 F4.1 arcsec DEs Declination (J2000)
27- 29 I3 --- [BLC2002] ? Galaxy optical counterpart number
31 I1 --- Group ? Group membership of the optical counterpart
if one is known
33- 39 F7.1 km/s RV ? Radial velocity of the galaxy
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 17-Jun-2002