J/ApJ/645/955 ChaMP serendipitous galaxy cluster survey (Barkhouse+, 2006)
ChaMP serendipitous galaxy cluster survey.
Barkhouse W.A., Green P.J., Vikhlinin A., Kim D.-W., Perley D., Cameron R.,
Silverman J., Mossman A., Burenin R., Jannuzi B.T., Kim M., Smith M.G.,
Smith R.C., Tananbaum H., Wilkes B.J.
<Astrophys. J., 645, 955-976 (2006)>
=2006ApJ...645..955B 2006ApJ...645..955B
ADC_Keywords: Surveys ; X-ray sources ; Redshifts
Keywords: galaxies: clusters: general - surveys - X-rays: galaxies: clusters
Abstract:
We present a survey of serendipitous extended X-ray sources and
optical cluster candidates from the Chandra Multiwavelength Project
(ChaMP). Our main goal is to make an unbiased comparison of X-ray and
optical cluster detection methods. In 130 archival Chandra pointings
covering 13deg2, we use a wavelet decomposition technique to detect
55 extended sources, of which 6 are nearby single galaxies. Our X-ray
cluster catalog reaches a typical flux limit of about
10-14ergs/cm2/s, with a median cluster core radius of 21". For 56
of the 130 X-ray fields, we use the ChaMP's deep NOAO 4m MOSAIC g',
r', and i' imaging to independently detect cluster candidates using a
Voronoi tessellation and percolation (VTP) method. Red-sequence
filtering decreases the galaxy fore- and background contamination and
provides photometric redshifts to z∼0.7. From the overlapping
6.1deg2 X-ray/optical imaging, we find 115 optical clusters (of
which 11% are in the X-ray catalog) and 28 X-ray clusters (of which
46% are in the optical VTP catalog).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 57 55 X-Ray detected extended sources
table3.dat 84 55 X-Ray properties of extended sources
table4.dat 62 102 VTP clusters with X-ray upper limits
table5.dat 91 55 *Published sources near X-ray positions
table6.dat 102 102 *Published sources near optical-only detections
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Note on table5.dat and table6.dat: Published references acquired from NED.
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See also:
J/ApJS/150/19 : ChaMP. I. First X-ray source catalog (Kim+, 2004)
J/ApJ/618/123 : Hard X-ray-emitting AGNs (Silverman+, 2005)
J/ApJ/644/829 : Chandra normal galaxies at intermediate redshift (Kim+, 2006)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- CXOMP Source Name, JHHMMSS.S+DDMMSS
18- 21 I4 --- ObsID Observation ID
23- 24 I2 h RAh Right ascension (J2000.0)
26- 27 I2 min RAm Right ascension (J2000.0)
29- 32 F4.1 s RAs Right ascension (J2000.0)
34 A1 --- DE- Declination sign (J2000.0)
35- 36 I2 deg DEd Declination (J2000.0)
38- 39 I2 arcmin DEm Declination (J2000.0)
41- 44 F4.1 arcsec DEs Declination (J2000.0)
46- 51 I6 s ExpTime Vignetting-corrected exposure time
53- 57 F5.2 10+20cm-2 NH Galactic NH values (from Stark et al.,
1992, See Cat. VIII/28)
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- CXOMP Source Name (JHHMMSS.s+DDMMSS)
18- 24 F7.2 ct Counts Counts
26- 31 F6.3 10-17W/m2 FX X-ray flux
33- 37 F5.3 10-17W/m2 e_FX rms uncertainty on FX
39- 45 F7.3 10+35W LX ?=- X-ray luminosity, in 10+42erg/s (1)
47- 52 F6.3 10+35W e_LX ?=- rms uncertainty on LX
54- 58 F5.2 arcsec rc Source core radius (2)
60- 64 F5.2 arcsec PSF Chandra PSF size at the location of extended
X-ray source (3)
66- 70 F5.2 arcmin OAA Off-axis angle
72- 77 F6.4 --- zsp ?=- Spectroscopic redshift (4)
78 A1 --- n_zsp [h] h: Redshift measured from our ChaMP
spectroscopic program
80- 84 F5.3 --- z ?=- Red-sequence filtered VTP corrected
redshifts (5)
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Note (1): Luminosities are calculated from spectroscopic redshifts unless
only VTP (Voronoi Tessellation and Percolation) estimates are available.
Note (2): Source core radius is estimated from the circular β model
fits. The uncertainty in rc is on the order of 10%-20%.
Note (3): The PSF is derived from the best-fit analytic relation between
the Gaussian sigma of point sources and is similar to the radius
encircling 50% of total counts for a monochromatic source at 0.75keV.
Note (4): Redshifts obtained from the literature have NED IDs listed in
Table 5. Typical spectroscopic redshift uncertainties are 0.0006.
Note (5): The dispersion of the VTP (Voronoi Tessellation and Percolation) i
redshifts about the spectroscopic values is 0.03.
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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- 3 I3 --- [BGV2006] Sequential number
5- 8 I4 --- ObsID Observation ID
10- 11 I2 h RAh Right ascension (J2000.0)
13- 14 I2 min RAm Right ascension (J2000.0)
16- 19 F4.1 s RAs Right ascension (J2000.0)
21 A1 --- DE- Declination sign (J2000.0)
22- 23 I2 deg DEd Declination (J2000.0)
25- 26 I2 arcmin DEm Declination (J2000.0)
28- 31 F4.1 arcsec DEs Declination (J2000.0)
33- 37 F5.3 --- z Corrected redshift (1)
38 A1 --- n_z [de] Redshift origin (2)
40- 41 A2 --- l_FX [≤ ] Limit flag on FX
42- 46 F5.3 --- FX X-ray flux (3)
49- 50 A2 --- l_LX [≤ ] Limit flag on LX
51- 56 F6.3 10+35W LX X-ray luminosity, in 10+42erg/s (3)
58- 62 F5.2 arcsec PSF Chandra PSF size at the location of optically
detected source (4)
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Note (1): Corrected redshifts estimated from red-sequence VTP (Voronoi
Tessellation and Percolation) unless otherwise noted.
Note (2): Note as follows:
d = Redshift measurement from NED
e = Redshift measurement from ChaMP spectroscopic program
Note (3): X-ray fluxes and luminosities are 3σ upper limits
for cluster candidates not detected in X-rays.
Note (4): The PSF is derived from the best-fit analytic relation between
the Gaussian sigma of point sources and is similar to the radius
encircling 50% of total counts for a monochromatic source at 0.75keV.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- CXOMP Source Name (JHHMMSS.s+DDMMSS)
18- 48 A31 --- Name Published ID (1)
50- 88 A39 --- Com Comments (2)
90- 91 I2 arcsec Dist ? Distance from extended X-ray centroid
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Note (1): Blank field if published sources >2' from object position.
Note (2): Available redshifts tabulated in Table 3.
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [BGV2006] Sequential number
5- 35 A31 --- Name Published ID (1)
37-102 A66 --- Com Comments
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Note (1): Blank field if published sources >2' from object position.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 05-Oct-2007