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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
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:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 85 153 The X-ray spectral fitting results for the 153 sources of our XMM-Newton/SDSS sample
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
Bytes Format Units Label Explanations
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)
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
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
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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