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J/AJ/123/3018       Redshifts of radio-selected poor clusters   (Miller+, 2002)

Redshifts for a sample of radio-selected poor clusters. Miller N.A., Ledlow M.J., Owen F.N., Hill J.M. <Astron. J. 123, 3018 (2002)> =2002AJ....123.3018M
ADC_Keywords: Clusters, galaxy ; Radio sources ; Redshifts Keywords: galaxies: active - galaxies: clusters: general - galaxies: distances and redshifts Abstract: Multifiber optical spectroscopy has been performed on galaxies in the vicinity of strong, nearby radio galaxies. These radio galaxies were selected from the 3CR and B2 catalogs based on their exclusion from the Abell catalog, which is puzzling given the hypothesis that an external medium is required to confine the radio plasma of such galaxies. Velocities derived from the spectra were used to confirm the existence of groups and poor clusters in the fields of most of the radio galaxies. We find that all radio galaxies with classical Fanaroff-Riley type I morphologies prove to reside in clusters, whereas the other radio galaxies often appear to be recent galaxy-galaxy mergers in regions of low galaxy density. These findings confirm the earlier result that the existence of extended X-ray emission combined with a statistical excess of neighboring galaxies can be used to identify poor clusters associated with radio galaxies. Description: The complete sample is composed of 25 radio galaxies drawn from the 3CRR (Laing, Riley, & Longair, 1983MNRAS.204..151L) and Wall & Peacock (1985, Cat. J/MNRAS/216/173) catalogs, plus 24 additional radio galaxies drawn from the B2 catalog (Colla et al., 1970 & 1972, Cat. VIII/36). The B2 sources are generally of lower radio luminosity but were added because the declination range of that survey made them excellent targets for observation at Kitt Peak. The radio galaxies were required to be nearby (z<0.06 for the 3CRR and Wall & Peacock galaxies, z<0.04 for the B2 galaxies) and not members of Abell clusters. We report on a subset of 25 of these radio galaxies in this paper. The remainder were unobservable because of declination limits of the telescope (six sources) and observing time lost because of weather. The full sample of radio galaxies and comments on their properties may be found in Table 1. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 93 49 3C and B2 non-Abell cluster radio galaxies refs.dat 69 13 References table2.dat 117 369 3C/B2 cluster member velocities table3.dat 117 95 Foreground and background galaxy velocities
See also: VIII/36 : The Second Bologna Survey (Colla+ 1970-1974) J/MNRAS/216/173 : Bright extragalactic radio sources at 2.7 GHz (Wall+, 1985) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 12 A12 --- Source Radio galaxy name 17- 18 I2 h RAh Right ascension (J2000.0) 20- 21 I2 min RAm Right ascension (J2000.0) 23- 24 I2 s RAs Right ascension (J2000.0) 26 A1 --- DE- Declination sign (J2000.0) 27- 28 I2 deg DEd Declination (J2000.0) 30- 31 I2 arcmin DEm Declination (J2000.0) 33- 34 I2 arcsec DEs Declination (J2000.0) 37- 41 F5.3 --- z Redshift 43- 45 A3 --- Obs [Yes No] Indicates whether spectroscopic observations of the radio galaxy field are included in this paper 46 A1 --- n_Obs [ab] Note on Obs (1) 49- 85 A37 --- Com Radio morphology and brief comments 88- 93 A6 --- Refs References for the radio morphology, in refs.dat file
Note (1): Notes as follows: a = Below declination limit of telescope b = Above declination limit of telescope
Byte-by-byte Description of file: refs.dat
Bytes Format Units Label Explanations
1- 2 I2 --- Ref Reference code 4- 22 A19 --- BibCode BibCode 24- 48 A25 --- Aut Author's name 50- 69 A20 --- Com Comments
Byte-by-byte Description of file: table2.dat table3.dat
Bytes Format Units Label Explanations
1- 12 A12 --- Source Radio galaxy name (G1) (1) 14- 15 I2 h RAh Galaxy right ascension (J2000.0) (G1) 17- 18 I2 min RAm Galaxy right ascension (J2000.0) (G1) 20- 23 F4.1 s RAs Galaxy right ascension (J2000.0) (G1) 25 A1 --- DE- Galaxy declination sign (J2000.0) (G1) 26- 27 I2 deg DEd Galaxy declination (J2000.0) (G1) 29- 30 I2 arcmin DEm Galaxy declination (J2000.0) (G1) 32- 33 I2 arcsec DEs Galaxy declination (J2000.0) (G1) 36- 40 I5 km/s cz ? This study heliocentric velocity from cross-correlation of emission lines 42- 44 I3 km/s e_cz ? rms uncertainty on cz 45 A1 --- n_cz [c] Note on cz (2) 47- 51 I5 km/s cz2 ? Prior studies heliocentric velocity, as reported in NED 53- 55 I3 km/s e_cz2 ? rms uncertainty on cz2 56 A1 --- n_cz2 [a] a: Velocity data from Ledlow et al., 1996AJ....112..388L 58-117 A60 --- EmLines Emission lines present (3)
Note (1): In original table2, 1651+351 was misprint for 1615+351. Note (2): Member of an identified cluster from the ROSAT All-Sky Survey, RX J1652.6+4011 (Boehringer et al., 2000, Cat. J/ApJS/129/435). The cluster is also in the Abell catalog, as Abell 2235. Note (3): If in parentheses, the reported velocity is based on cross-correlation of the absorption lines.
Global notes: Note (G1): Identification of galaxies in Simbad: In table 2, [MLO2002] B2 HHMM+DD JHHMMSS.s+DDMMSS or [MLO2002] 3C NNN JHHMMSS.s+DDMMSS In table 3, [MLO2002] JHHMMSS.s+DDMMSS
History: From electronic version of the journal
(End) James Marcout, Patricia Bauer [CDS] 24-Apr-2003
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

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