J/ApJS/172/368 XMM-Newton survey in COSMOS field. IV. (Mainieri+, 2007)
The XMM-Newton wide-field survey in the COSMOS field.
IV. X-ray spectral properties of active galactic nuclei.
Mainieri V., Hasinger G., Cappelluti N., Brusa M., Brunner H., Civano F.,
Comastri A., Elvis M., Finoguenov A., Fiore F., Gilli R., Lehmann I.,
Silverman J., Tasca L., Vignali C., Zamorani G., Schinnerer E., Impey C.,
Trump J., Lilly S., Maier C., Griffiths R.E., Miyaji T., Capak P.,
Koekemoer A., Scoville N., Shopbell P., Taniguchi Y.
<Astrophys. J. Suppl. Ser., 172, 368-382 (2007)>
=2007ApJS..172..368M 2007ApJS..172..368M
ADC_Keywords: Surveys ; X-ray sources ; Active gal. nuclei ; Redshifts
Keywords: galaxies: active - surveys - X-rays: diffuse background -
X-rays: galaxies - X-rays: general
Abstract:
We present a detailed spectral analysis of pointlike X-ray sources in
the XMM-Newton COSMOS field. Our sample of 135 sources only includes
those that have more than 100 net counts in the 0.3-10keV energy band
and have been identified through optical spectroscopy. The majority of
the sources are well described by a simple power-law model with either
no absorption (76%) or a significant intrinsic, absorbing column
(20%). The remaining ∼4% of the sources require a more complex
modeling by incorporating additional components to the power law. For
sources with more than 180 net counts (bright sample), we allowed both
the photon spectral index Gamma and the equivalent hydrogen column NH
to be free parameters. For fainter sources, we fix Gamma to the
average value and allow NH to vary. The mean spectral index of the 82
sources in the bright sample is <Gamma≥2.06±0.08, with an intrinsic
dispersion of ∼0.24. Each of these sources has fractional errors on
the value of Gamma below 20%. As expected, the distribution of
intrinsic absorbing column densities is markedly different between
AGNs with or without broad optical emission lines. We find within our
sample four type 2 QSO candidates (LX>1044erg/s, NH>1022cm-2),
with a spectral energy distribution well reproduced by a composite
Seyfert 2 spectrum, that demonstrates the strength of the wide-field
COSMOS XMM-Newton survey to detect these rare and underrepresented
sources. In addition, we have identified a Compton-thick
(NH>1.5x1024cm-2) AGN at z=0.1248. Its X-ray spectrum is well
fitted by a pure reflection model and a significant Fe Kα line
at rest-frame energy of 6.4keV.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 151 135 X-Ray Spectral Fit Parameters
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See also:
B/xmm : XMM-Newton Observation Log (XMM-Newton SOC, 2007)
II/284 : COSMOS Multi-Wavelength Photometry Catalog (Capak+, 2007)
J/ApJS/172/29 : XMM-Newton survey in COSMOS field. I. (Hasinger+, 2007)
J/ApJS/172/182 : Cluster of galaxies in XMM-COSMOS (Finoguenov+ 2007)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [XMMC]
6- 24 A19 --- XMMC XMMC designation (JHHMMSS.ss+DDMMSS.s)
26- 29 I4 --- XID Internal reference number, from Hasinger
et al., Cat. J/ApJS/172/29,
XMMC NNNN in Simbad
30 A1 --- n_XID [i] Individual note (1)
32- 33 I2 h RAh X-ray right ascension (J2000.0)
35- 36 I2 min RAm X-ray right ascension (J2000.0)
38- 42 F5.2 s RAs X-ray right ascension (J2000.0)
44 A1 --- DE- X-ray declination sign (J2000.0)
45 I1 deg DEd X-ray declination (J2000.0)
47- 48 I2 arcmin DEm X-ray declination (J2000.0)
50- 54 F5.2 arcsec DEs X-ray declination (J2000.0)
56- 59 I4 ct Count Net PN counts in 0.3-10keV energy band
61- 65 F5.3 --- z Spectroscopic redshift of the most
likely optical counterpart (2)
67- 75 A9 --- Model Best-fit model as discussed in Sect. 4
77- 80 F4.2 --- Gamma ? Power-law photon index
82- 85 F4.2 --- GammaU ? Upper value of Gamma interval
87- 90 F4.2 --- GammaL ? Lower value of Gamma interval
92 A1 --- l_logNH Limit flag on NH
93- 97 F5.2 [cm-2] logNH ? Intrinsic hydrogen column density
99-103 F5.2 [cm-2] logNHU ? Upper value of NH interval
105-109 F5.2 [cm-2] logNHL ? Lower value of NH interval
111-117 F7.2 10-19W/m2 FXs X-ray flux from the spectral fit in the
soft (0.5-2keV) rest-frame energy band
119-125 F7.2 10-19W/m2 FXh X-ray flux from the spectral fit in the
hard (2-10keV) rest-frame energy band
127-133 F7.2 10-19W/m2 FXtot X-ray flux from the spectral fit in the
total (0.5-10keV) rest-frame energy band
135-139 F5.2 [10-7W] logLXs Absorption-corrected X-ray luminosities
in the 0.5-2keV rest-frame energy band
141-145 F5.2 [10-7W] logLXh Absorption-corrected X-ray luminosities
in the 2-10keV rest-frame energy band
147-151 F5.2 [10-7W] logLXtot Absorption-corrected X-ray luminosities
in the 0.5-10keV rest-frame energy band
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Note (1): A power-law model is not a good representation of this source
(see Sect. 4.1).
Note (2): For details see Brusa et al., 2007ApJS..172..353B 2007ApJS..172..353B.
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History:
From electronic version of the journal
References:
Finoguenov et al., 2007ApJS..172..182F 2007ApJS..172..182F, Cat. J/ApJS/172/182
Hasinger et al., Paper I 2007ApJS..172...29H 2007ApJS..172...29H, Cat. J/ApJS/172/29
Cappelluti et al., Paper II 2007ApJS..172..341C 2007ApJS..172..341C
Brusa et al., Paper III 2007ApJS..172..353B 2007ApJS..172..353B
Miyaji et al., Paper V 2007ApJS..172..396M 2007ApJS..172..396M
(End) Patricia Vannier [CDS] 04-Mar-2008