J/A+A/459/693 XMM/CDFS AGN intrinsic absorption (Akylas+, 2006)
XMM-Newton and Chandra measurements of the AGN intrinsic absorption:
dependence on luminosity and redshift.
Akylas A., Georgantopoulos I., Georgakakis A., Kitsionas S.,
Hatziminaoglou E.
<Astron. Astrophys., 459, 693-701 (2006)>
=2006A&A...459..693A 2006A&A...459..693A
ADC_Keywords: Surveys ; Active gal. nuclei ; X-ray sources
Keywords: surveys - X-rays: galaxies - X-rays: general
Abstract:
We combine bright XMM-Newton data with the Chandra Deep Field South
observations to explore the behavior of the intrinsic AGN absorption,
as a function of redshift and luminosity. Our sample consists of 359
sources selected in the hard 2-8keV band, spanning the flux range
6x10-16-3x10-13erg/cm2/s with a high rate of spectroscopic or
photometric redshift completeness (100 and 85 per cent respectively
for the Chandra and XMM-Newton data). We derive the column density
values using X-ray spectral fits. We find that the fraction of
obscured AGN falls with increasing luminosity in agreement with
previous findings. The fraction of obscured AGN shows an apparent
increase at high redshifts (z>2). Simulations show that this effect
can most probably be attributed to the fact that at high redshifts the
column densities are overestimated.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 85 153 The X-ray spectral fitting results for the 153
sources of our XMM-Newton/SDSS sample
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See also:
J/A+A/444/79 : XMM obs. of Lockman Hole brightest AGNs (Mateos+, 2005)
J/MNRAS/366/171 : Red AGN in XMM/SDSS fields (Georgakakis+, 2006)
J/A+A/451/457 : X-ray properties of AGN in CDFS (Tozzi+, 2006)
J/ApJ/640/167 : AGNs and ULIRGs in the CDF-South (Alonso-Herrero+, 2006)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [AGG2006] [1,153]+ Sequential number
5- 11 F7.3 deg RAdeg Right ascension in decimal degrees (J2000)
13- 19 F7.3 deg DEdeg Declination sign in decimal degrees (J2000)
21- 24 F4.2 --- Gamma Spectral index (1)
26- 29 F4.2 --- E_Gamma ? Error on Gamma (upper limit)
31- 34 F4.2 --- e_Gamma ? Error on Gamma (lower limit)
36 A1 --- l_NH Limit flag on NH
37- 43 F7.3 10+22cm-2 NH Observed hydrogen column density,
best fit value
44- 48 F5.2 10+22cm-2 E_NH ? Error on NH (upper limit)
50- 53 F4.2 10+22cm-2 e_NH ? Error on NH (lower limit)
55- 59 F5.2 10-17W/m2 F2-8keV Intrinsic 2-8keV flux
61- 64 F4.2 --- z ?=- Redshift
66- 70 F5.2 10+20cm-2 NHgal Galactic column density in the directions
of the observed field
72- 77 F6.2 10+22cm-2 NHint Intrinsic rest frame column density
79- 83 F5.2 [10-7W] LogLum Logarithm of intrinsic 2-8keV luminosity
85 I1 --- ID [1/3] Flag for optical counterpart (2)
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Note (1): When the photon index is fixed to 1.8 the spectral fittings
are performed using the C-statistic technique.
Note (2): Optical counterpart flag as follows:
1 = spectroscopic optical counterpart
2 = photometric optical counterpart
3 = absence of an optical counterpart
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History:
* 18-May-2007: From electronic version of the journal
* 31-Jul-2007: table2.dat: the Sequential number #88 was repeated;
the second occurence was changed to 89.
(End) Patricia Vannier [CDS] 18-May-2007