J/AJ/135/1505 CDFs AGNs X-ray power-law photon index (Saez+, 2008)
Confirmation of a correlation between the X-ray luminosity and spectral slope of
active galactic nuclei in the Chandra Deep Fields.
Saez C., Chartas G., Brandt W.N., Lehmer B.D., Bauer F.E., Dai X.,
Garmire G.P.
<Astron. J., 135, 1505-1522 (2008)>
=2008AJ....135.1505S 2008AJ....135.1505S
ADC_Keywords: Active gal. nuclei ; Redshifts ; X-ray sources
Keywords: cosmology: observations - galaxies: active - galaxies: statistics -
X-rays: galaxies
Abstract:
We present results from a statistical analysis of 173 bright
radio-quiet active galactic nuclei (AGNs) selected from the Chandra
Deep Field-North and Chandra Deep Field-South surveys (hereafter,
CDFs) in the redshift range of 0.1≲≲4. We find that the X-ray
power-law photon index (Γ) of radio-quiet AGNs is correlated with
their 2-10keV rest-frame X-ray luminosity (LX) at the >99.5%
confidence level in two redshift bins: 0.3~<z~<0.96, and 1.5~<z~<3.3
and is slightly less significant in the redshift bin 0.96~<z~<1.5.
Description:
Our sources were selected from the CDFs, currently the two deepest
X-ray surveys. The on-axis sensitivity limits for the CDF-N are
∼2.5x10-17erg/cm2/s (0.5-2.0keV) and ∼1.4x10-16erg/cm2/s
(2-8keV).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 107 317 Properties of our sample of RQ AGNs selected
from the Chandra Deep Field Surveys
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See also:
J/AJ/126/539 : The Chandra Deep Fields North and South (Alexander+, 2003)
J/ApJS/155/73 : Photometric redshifts of X-ray sources in CDF-S (Zheng+, 2004)
J/ApJ/640/167 : AGNs and ULIRGs in the CDF-South (Alonso-Herrero+, 2006)
J/A+A/497/81 : Variability-selected AGN in CDFS (Boutsia+, 2009)
J/A+A/507/1277 : Multiwavelength photometry of CDFS X-ray sources (Brusa+ 2009)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1 A1 --- n_CXO [OR] Type of fit (1)
3- 5 A3 --- --- [CXO]
6- 24 A19 --- CXO The X-ray identification,
CXOJHHMMSS.ss+DDMMSS.s
26- 30 F5.3 --- z Redshift from the literature (see Sec. 2)
32 A1 --- f_z [sp] spectroscopic or photometric redshift
34- 40 F7.1 ct Cts Background subtracted source counts (3)
42- 45 F4.2 --- Gamma X-ray power-law photon index Γ
47- 50 F4.2 --- E_Gamma Upper limit error in Gamma
52- 55 F4.2 --- e_Gamma Lower limit error in Gamma
57- 61 F5.2 10+22cm-2 NH ? Hydrogen column density
63- 67 F5.2 10+22cm-2 E_NH ? Upper limit error in NH
69- 73 F5.2 10+22cm-2 e_NH ? Lower limit error in NH
75- 79 F5.2 [10-7W] logL Log of the 2-10keV X-ray luminosity,
in units of erg/s
81- 85 F5.1 --- Cstat Cash (1979ApJ...228..939C 1979ApJ...228..939C) C-statistic
87- 89 I3 --- dof Degrees of freedom
91-100 A10 --- Type Source classification (4)
102-107 A6 --- Model Model used (5)
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Note (1): CXO flag as follows:
O = based on fits performed in the 0.5-8 keV observed-frame
R = based on fits performed in the 2-10 keV rest-frame
Note (3): in the 0.5-8keV observed-frame band for fits performed in the
0.5-8keV observed-frame band and counts in the 2-10keV rest-frame band
for fits performed in the 2-10keV rest-frame band.
Note (4): Based on Bauer et al. (2004AJ....128.2048B 2004AJ....128.2048B), source
classifications from Section 4.1.1
(http://www.astro.psu.edu/~niel/hdf/hdf-chandra.html)
Note (5): Model used as follows:
PL = power-law (XSPEC model wabs(pow))
APL = absorbed-power-law (XSPEC model wabs*zwabs(pow))
PAPL = partially-absorbed-power-law (XSPEC model wabs*zpcfabs(pow))
IAPL = ionized-absorbed-power-law (XSPEC model wabs*absori(pow))
PL+EL = power-law + emission-line (XSPEC model wabs(pow+zgauss))
APL+EL = absorbed-power-law + emission-line
(XSPEC model wabs*zwabs*(pow+zgauss))
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 12-Oct-2010