J/AJ/128/1483 Optical properties of the CLASXS X-ray sample (Steffen+, 2004)
An optical catalog of the Chandra Large Area Synoptic X-ray Survey sources.
Steffen A.T., Barger A.J., Capak P., Cowie L.L., Mushotzky R.F., Yang Y.
<Astron. J., 128, 1483-1500 (2004)>
=2004AJ....128.1483S 2004AJ....128.1483S
ADC_Keywords: X-ray sources ; Photometry ; Redshifts
Keywords: X-rays: galaxies - X-rays: general
Abstract:
We present photometric and spectroscopic observations of the X-ray
sources detected in the wide-area, moderately deep Chandra Large Area
Synoptic X-ray Survey (CLASXS) of the Lockman Hole-Northwest field. We
have B, V, R, I, and z' photometry for 521 (99%) of the 525 sources in
the X-ray catalog and spectroscopic redshifts for 271 (52%), including
20 stars. We do not find evidence for redshift groupings of the X-ray
sources, like those found in the Chandra Deep Field surveys, because
of the larger solid angle covered by this survey. We separate the
X-ray sources by optical spectral type and examine the colors,
apparent and absolute magnitudes, and redshift distributions for the
broad-line and nonbroad-line active galactic nuclei. Combining our
wide-area survey with other Chandra and XMM-Newton hard X-ray surveys,
we find a definite lack of luminous, high accretion rate sources at
z<1, consistent with previous observations that showed that
supermassive black hole growth is dominated at low redshifts by
sources with low accretion rates.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 119 525 Optical Properties of the CLASXS X-Ray Sample
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See also:
J/AJ/128/1501 : CLASXS: X-ray catalog (Yang+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- CLASXS The Yang et al. (2004, Cat. J/AJ/128/1501)
number
5- 14 F10.6 deg RAdeg X-ray right ascension in decimal
degrees (J2000)
16- 23 F8.5 deg DEdeg X-ray declination in decimal
degrees (J2000)
25- 34 F10.6 deg ORAdeg ? Optical right ascension in decimal
degrees (J2000)
36- 43 F8.5 deg ODEdeg ? Optical declination in decimal
degrees (J2000)
45- 48 F4.1 arcmin R Smallest aim-point distance
51- 56 F6.3 aW/m2 SB ? The 0.5-2keV X-ray flux (1)
58- 64 F7.3 aW/m2 HB ? The 2-8keV X-ray flux (1)
66- 70 F5.1 mag Bmag ? Aperture-corrected Johnson B-band
AB magnitude (2)
72- 73 I2 --- f_Bmag [-1/1]? Limit flag on Bmag (3)
75- 79 F5.1 mag Vmag ? Aperture-corrected Johnson V-band
AB magnitude (2)
81- 82 I2 --- f_Vmag [-1/1]? Limit flag on Vmag (3)
84- 88 F5.1 mag Rcmag ? Aperture-corrected Cousins R-band
AB magnitude (2)
90- 91 I2 --- f_Rcmag [-1/1]? Limit flag on Rcmag (3)
93- 97 F5.1 mag Icmag ? Aperture-corrected Cousins I-band
AB magnitude (2)
99-100 I2 --- f_Icmag [-1/1]? Limit flag on Icmag (3)
102-106 F5.1 mag z'mag ? Aperture-corrected Sloan z'-band
AB magnitude (2)
108-109 I2 --- f_z'mag [-1/1]? Limit flag on z'mag (3)
112-116 F5.3 --- zspec ? Spectroscopic redshift
118-119 I2 --- f_zspec ? Flag on zspec (4)
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Note (1): From Yang et al. (2004, Cat. J/AJ/128/1501) in units of
10-15ergs/cm2/s. Negative values denote upper limits.
Note (2): In the AB magnitude system. An AB magnitude is defined by
mAB=-2.5log(fν)-48.60, where fν is the flux of the
source in units of ergs/cm2/s/Hz.
Note (3): Limit flag on B, V, R, I, and z' magnitudes, defined as follows:
0 = Not a limit;
-1 = Lower limit;
1 = Upper limit.
Note (4): Flag on zspec, with the following meaning:
-2 = Star;
-1 = Unobserved;
0 = Absorption-line system;
1 = Star-former;
2 = Seyfert 2 based on strong [O II] relative to Hβ or strong [Ne III]
relative to [O II];
3 = Seyfert 2 with [Ne V] or C IV in emission;
4 = Broad-line AGN (FWHM>1000km/s).
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 17-Feb-2005