J/MNRAS/274/75 Redshifts of ROSAT X-ray brightest clusters (Crawford+, 1995)
Optical spectroscopy of the ROSAT X-ray brightest clusters. II.
Crawford C.S., Edge A.C., Fabian A.C., Allen S.W., Bohringer H., Ebeling H.,
McMahon R.G., Voges W.
<Mon. Not. R. Astron. Soc. 274, 75 (1995)>
=1995MNRAS.274...75C 1995MNRAS.274...75C
ADC_Keywords: Clusters, galaxy ; X-ray sources ; Redshifts
Keywords: surveys - galaxies: clusters: general - cooling flows -
galaxies: elliptical and lenticular, cD - galaxies: stellar content -
X-rays: galaxies
Abstract:
We report results from the second stage of an optical follow-up study
aimed at determining new redshifts for clusters of galaxies selected
from the ROSAT All-Sky Survey. We review the optical properties of all
the clusters obtained so far in this programme, which comprises 71
clusters up to a redshift of 0.3. The fraction of central galaxies
exhibiting optical line emission and an excess blue continuum is 34%,
consistent with smaller, previous, X-ray samples. There is no trend
for this fraction to increase with redshift, although we find a clear
tendency for the strongest line emitters to have the bluest continua.
The probability of the presence of line emission and an excess blue
continuum is increased for those galaxies with associated radio
sources, although the strength of these features does not appear to be
related to the power of the radio emission.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 84 48 New redshifts
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See also:
IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999)
IX/29 : ROSAT All-Sky Survey Faint Source Catalog (Voges+ 2000)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [RX]
4- 15 A12 --- RXJ ROSAT denomination (based on J2000 position)
17 I1 --- Note [1/2]? Rank of the X-ray galaxy (1)
19 A1 --- n_Name [+] +: Not a central dominant galaxy (2)
20- 29 A10 --- Name Optical name
31 I1 --- Note2 [1/2]? Rank of the optical galaxy (1)
33- 34 I2 h RAh Optical right ascension (1950)
36- 37 I2 min RAm Optical right ascension (1950)
39- 42 F4.1 s RAs Optical right ascension (1950)
44 A1 --- DE- Optical declination sign (1950)
45- 46 I2 deg DEd Optical declination (1950)
48- 49 I2 arcmin DEm Optical declination (1950)
51- 52 I2 arcsec DEs Optical declination (1950)
54 A1 --- u_zem [+] Note on zem (3)
55- 59 F5.3 --- zem ? Emission redshift
61 A1 --- u_zabs [+] Note on zabs (3)
62- 66 F5.3 --- zabs ? Absorption redshift
69- 72 F4.1 0.1nm EWHalpha ? Hα equivalent width (4)
74- 77 F4.2 0.1nm e_EWHalpha ? rms uncertainty on EWHalpha
79- 81 I3 mJy S1.4GHz ? Radio flux a 1.4GHz
82 A1 --- n_S1.4GHz [*] *: Radio fluxes extrapolated from
4.85GHz (5)
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Note (1): The most likely central dominant galaxy in RX J1000.5+4409 is
galaxy (1), and in A2034 it is galaxy (2). In A773, A2552 and A2627
the two galaxies observed appear equally dominant.
Note (2): All are central dominant galaxies in clusters, apart from
III Zw 054 (marked by a +) which is a galaxy.
Note (3): The redshifts marked by a + should be regarded as provisional
due to poor signal-to-noise spectra.
Note (4): Where no equivalent width is given for Hα, this is because
it coincided with sky absorption bands in the spectrum.
Note (5): Radio fluxes marked with an asterisk are extrapolated from 4.85GHz,
assuming a spectral index of -1.
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Nomenclature Notes:
Sources are identified as [CEF95] HHMMSS.s+DDMMSS, with optical coordinates.
History:
Prepared via OCR at CDS.
References:
Allem et al., Paper I 1992MNRAS.259...67A 1992MNRAS.259...67A
(End) James Marcout, Patricia Bauer [CDS] 29-Jul-2002