J/ApJ/580/774 X-ray cluster of galaxies behind the Milky way (Ebeling+, 2002)
A systematic X-ray search for clusters of galaxies behind the Milky way.
Ebeling H., Mullis C.R., Tully R.B.
<Astrophys. J. 580, 774 (2002)>
=2002ApJ...580..774E 2002ApJ...580..774E
ADC_Keywords: Clusters, galaxy ; X-ray sources ; Redshifts
Keywords: galaxies: clusters: general - surveys - X-rays: galaxies: clusters
Abstract:
We report on the design and status of the Clusters in the Zone of
Avoidance (CIZA) project, the first systematic X-ray search for
clusters of galaxies behind the Milky Way.
Our project, Clusters in the Zone of Avoidance (CIZA), uses X-ray data
from the RASS for the initial cluster candidate selection and
subsequent optical and NIR observations to confirm or refute the
cluster nature of all selected candidates.
We demonstrate that an X-ray survey can find galaxy clusters at low
Galactic latitude where optical searches are inefficient because of
massive obscuration and extinction problems. We discuss the rationale
for such a survey in the context of large-scale structure studies and
describe in detail the combined X-ray/optical/NIR approach used by
CIZA to identify clusters of galaxies at |b|<20°, a region of the
sky that has traditionally been excluded from earlier cluster
catalogs. So far, CIZA has identified and spectroscopically confirmed
137 galaxy clusters in what used to be the zone of avoidance;
additional clusters have been confirmed in imaging observations and
await spectroscopic observation. We present a catalog of the 73 X-ray
brightest CIZA clusters, 53 (73%) of which are new discoveries.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 132 73 Catalog of the 73 X-Ray brightest clusters from
the CIZA survey (Clusters In the Zone of Avoidance)
refs.dat 115 19 References
--------------------------------------------------------------------------------
See also:
IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999)
IX/29 : ROSAT All-Sky Survey Faint Source Catalog (Voges+ 2000)
VII/209 : Galaxies Behind the Milky Way (Saito+ 1990-91; Roman+ 1996-98)
J/A+A/387/1 : DENIS galaxies behind the Milky Way (Vauglin+, 2002)
J/ApJS/89/57 : IRAS galaxies behind southern Milky Way (Yamada+, 1993)
J/A+AS/104/529 : IRAS galaxies behind the Milky Way (Takata+ 1994)
J/A+AS/141/123 : Galaxies behind Southern Milky Way (Kraan-Korteweg 2000)
J/ApJS/112/245 : Redshift survey for IRAS galaxies (Nakanishi+ 1997)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- --- [CIZA]
6- 17 A12 --- CIZA CIZA designation (JHHMM.m+DDMM)
19- 40 A22 --- Name Other name
43- 44 I2 h RAh Cluster X-ray centroid
Right ascension (J2000.0)
46- 47 I2 min RAm Cluster X-ray centroid
Right ascension (J2000.0)
49- 52 F4.1 s RAs Cluster X-ray centroid
Right ascension (J2000.0)
54 A1 --- DE- Cluster X-ray centroid
Declination sign (J2000.0)
55- 56 I2 deg DEd Cluster X-ray centroid Declination (J2000.0)
58- 59 I2 arcmin DEm Cluster X-ray centroid Declination (J2000.0)
61- 62 I2 arcsec DEs Cluster X-ray centroid Declination (J2000.0)
64- 70 F7.3 deg GLON Galacitc longitude
72- 78 F7.3 deg GLAT Galactic latitude
80- 86 F7.4 ct/s CR Total cluster count rate in ROSAT broad band
88- 93 F6.4 ct/s e_CR rms uncertainty on CR
95- 99 F5.2 10+20cm-2 NH Equivalent neutral hydrogen column density (1)
101-106 F6.2 10-15W/m2 FX Total cluster flux at 0.1-2.4keV (2)
108-113 F6.4 --- z Redshift
114 A1 --- u_z [)] Uncertainty flag on z
116-120 F5.2 10+37W LX Total cluster X-ray luminosity at 0.1-2.4keV
in units of 1044h50-2erg/s
122-131 A10 --- r_z ? Redshift references, separated by comma
132 A1 --- n_z [e] e: estimated redshift
--------------------------------------------------------------------------------
Note (1): From Dickey & Lockman (1990ARA&A..28..215D 1990ARA&A..28..215D)
Note (2): Asssuming a metallicity of 0.3 solar and a cluster gas temperature
consistent with the LX-T relation of
White, Jones, & Forman (1997MNRAS.292..419W 1997MNRAS.292..419W)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: refs.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Ref Reference number
4- 22 A19 --- BibCode BibCode
24- 44 A21 --- Aut Author's name
49-115 A67 --- Com Comments
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) James Marcout, Patricia Bauer [CDS] 06-Feb-2003