J/MNRAS/337/256 Galaxy in low X-ray luminosity clusters (Balogh+, 2002)
Galaxy properties in low X-ray luminosity clusters at z=0.25.
Balogh M., Bower R.G., Smail I., Ziegler B.L., Davies R.L., Gaztelu A.,
Fritz A.
<Mon. Not. R. Astron. Soc. 337, 256 (2002)>
=2002MNRAS.337..256B 2002MNRAS.337..256B
ADC_Keywords: Clusters, galaxy ; X-ray sources ; Velocity dispersion ;
Equivalent widths
Keywords: Galaxies: clusters: general
Abstract:
We present the first spectroscopic survey of intrinsically low X-ray
luminosity clusters at z≫0, with Hubble Space Telescope (HST) WFPC2
imaging and spectroscopy from Calar Alto and WHT-LDSS2. We study 172
confirmed cluster members in a sample of ten clusters at 0.23<z<0.3,
with LX≲4x1043h-2erg/s[0.1-2.4keV]. The core of each cluster is
imaged with WFPC2 in the F702W filter, and the spectroscopic sample is
statistically complete to Mr~-19.0+5logh, within an 11' (∼1.8h-1Mpc)
field. The clusters are dynamically well-separated from the
surrounding field and most have velocity distributions consistent with
Gaussians. The velocity dispersions range from 350-850km/s, consistent
with the local LX-σ correlation. All 10 clusters host a
bright, giant elliptical galaxy without emission lines, near the
centre of the X-ray emission. We measure the equivalent width of two
nebular emission lines, [O II] and Hα, and the Hδ
absorption line to classify the cluster members spectrally. Galaxy
morphologies are measured from the HST images, using the
two-dimensional surface-brightness fitting software GIM2D.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 61 10 Properties of the 10 clusters
table4.dat 100 173 Properties of cluster members
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See also:
J/ApJS/56/403 : X-ray survey of clusters of galaxies. IV. (Kowalski+, 1984)
J/ApJS/129/435 : NORAS galaxy cluster survey. I. (Bohringer+, 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 --- --- [Cl]
4- 10 A7 --- Cluster Cluster name (HHMM+DD)
11 A1 --- m_Cluster [ab] Multiplicity index on Cluster
13- 14 I2 h RAh Right ascension (J2000)
16- 17 I2 min RAm Right ascension (J2000)
19- 20 I2 s RAs Right ascension (J2000)
22 A1 --- DE- Declination sign (J2000)
23- 24 I2 deg DEd Declination (J2000)
26- 27 I2 arcmin DEm Declination (J2000)
29- 30 I2 arcsec DEs Declination (J2000)
33- 34 I2 --- Nmemb Number of members
36- 41 F6.4 --- Mean redshift
43- 45 I3 km/s sigma Velocity dispersion
47- 50 I4 km/s e_sigma rms uncertainty on sigma
52- 55 F4.2 10+36W LX X-ray luminosity in 1043h-2erg/s
56 A1 --- n_LX [b] Note for Cl 1444+63 (1)
58- 61 F4.2 --- Comp Completeness (2)
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Note (1): Cl 1444+63 is only detected as a single X-ray source;
this LX presumably includes contribution from both clusters.
Note (2): Computed for galaxies more than 1 magnitude brighter than
the faintest galaxy with a redshift in that cluster.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 7 A7 ---- Cluster Cluster designation (HHMM+DD) (2)
8- 10 A3 --- m_Cluster [a/b ] Multilicity index on Cluster
13- 15 I3 --- Gal Galaxy identification number (1)
16 A1 --- n_Gal [a] a: Central, giant elliptical galaxy
18- 21 F4.1 mag rmag r magnitude
24- 29 F6.4 --- z Redshfit
31- 32 I2 h RAh Right ascension (J2000)
34- 35 I2 min RAm Right ascension (J2000)
37- 42 F6.3 s RAs Right ascension (J2000)
44 A1 --- DE- Declination sign (J2000)
45- 46 I2 deg DEd Declination (J2000)
48- 49 I2 arcmin DEm Declination (J2000)
51- 56 F6.3 arcsec DEs Declination (J2000)
58- 61 F4.2 --- B/T ? Bulge to total light ratio (GIM2D
parameter) in measurement for galaxies
observed with HST
64- 67 F4.1 --- S/N Signal-to-noise ratio
69- 73 F5.1 0.1nm EW0([OII]) ? [O II] dereddened equivalent width
75- 78 F4.1 0.1nm e_EW0([OII]) ? rms uncertainty on EW0([OII])
81- 84 F4.1 0.1nm EW0(Hdelta) ? Hδ dereddened equivalent width
86- 88 F3.1 0.1nm e_EW0(Hdelta) ? rms uncertainty on EW0(Hdelta)
90- 94 F5.1 0.1nm EW0(Ha+[NII]) ? Hα+[N II] dereddened equivalent
width
97-100 F4.1 0.1nm e_EW0(Ha+[NII]) ? rms uncertainty on EW0(Ha+[NII])
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Note (1): Identification number from the photometric catalogue.
Serendipitous observations not in the original catalogue have an
identification number of -99.
In Simbad, galaxies are identified as [BBS2002] Cl JHHMMa NNN
Note (2): the original table copntained only the RA part of the cluster
name; the full cluster name (HHMM+DD) was added at CDS.
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History:
From electronic version of the journal
05-Jun-2003: Two duplicated lines supressed in table4.
(End) James Marcout, Patricia Bauer [CDS] 07-Jan-2003