J/ApJ/728/58 Swift-BAT survey of AGNs (Burlon+, 2011)
Three-year Swift-BAT survey of active galactic nuclei: reconciling theory and
observations?
Burlon D., Ajello M., Greiner J., Comastri A., Merloni A., Gehrels N.
<Astrophys. J., 728, 58 (2011)>
=2011ApJ...728...58B 2011ApJ...728...58B
ADC_Keywords: Active gal. nuclei ; X-ray sources
Keywords: galaxies: active - radiation mechanisms: non-thermal - X-rays: general
Abstract:
We derive and analyze the active galactic nuclei (AGNs) absorption
distribution using a complete sample of AGNs detected by Swift-BAT in
the first three years of the survey. The fraction of Compton-thick
AGNs represents only 4.6% of the total AGN population detected by
Swift-BAT. However, we show that once corrected for the bias against
the detection of very absorbed sources the real intrinsic fraction of
Compton-thick AGNs is 20+9-6%. We proved for the first time (also
in the Burst Alert Telescope (BAT) band) that the anti-correlation of
the fraction of absorbed AGNs and luminosity is tightly connected to
the different behavior of the X-ray luminosity functions (XLFs) of
absorbed and unabsorbed AGNs. This points toward a difference between
the two subsamples of objects with absorbed AGNs being, on average,
intrinsically less luminous than unobscured ones. Moreover, the XLFs
show that the fraction of obscured AGNs might also decrease at very
low luminosity.
Description:
The sample used in this work is the collection of non-blazar AGNs
detected by BAT during the first three years, more precisely between
2005 March and 2008 March. This sample is part of the one used in
Ajello et al. (2009, Cat. J/ApJ/699/603) which comprises all sources
detected by BAT at high (|b|>15°) Galactic latitude and with a
signal-to-noise ratio (S/N) exceeding 5σ. All the 199 sources
which are identified as non-blazar AGNs (e.g., Seyferts) constitute
the sample used in this work.
We extracted Swift-BAT spectra and spectra in the 0.3-10keV band
using archival XMM-Newton and Swift-XRT data.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table5.dat 110 199 Swift sample of AGNs
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See also:
J/A+A/528/A122 : SwiftFT catalog (Puccetti+, 2011)
J/A+A/510/A48 : Palermo Swift-BAT Hard X-ray Catalogue (Cusumano+, 2010)
J/ApJ/699/603 : Evolution of Swift/BAT blazars (Ajello+, 2009)
J/A+A/495/421 : Catalog of AGN in XMM-Newton archive (CAIXA) (Bianchi+, 2009)
J/ApJ/681/113 : Swift BAT survey of AGNs (Tueller+, 2008)
J/ApJ/678/102 : BAT X-ray survey. I. (Ajello+, 2008)
J/A+A/487/119 : AGN in XMM-Newton Hard Bright Survey (Della Ceca+, 2008)
J/A+A/474/473 : XMM-LSS survey: AGN classifications (Garcet+, 2007)
J/ApJ/633/L77 : SWIFT/BAT detections of AGN (Markwardt+, 2005)
J/MNRAS/360/782 : X-ray-selected normal galaxies (Georgantopoulos+, 2005)
J/A+A/309/81 : X-ray properties of AGN (Wang+, 1996)
Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- SWIFT SWIFT name (JHHMM.m+DDMM)
14- 20 F7.3 deg RAdeg Right ascension in decimal degrees (J2000)
22- 28 F7.3 deg DEdeg Declination in decimal degrees (J2000)
30- 34 F5.2 aW/cm2 Flux [0.76/49.77] BAT flux in the 15-55keV energy
band in 10-11erg/cm2/s units
36- 39 F4.2 aW/cm2 e_Flux Flux uncertainty
41- 45 F5.1 --- S/N [5/187.6] Signal-to-noise ratio
47- 72 A26 --- Name SIMBAD other name
74- 79 A6 --- Type Optical type (GALAXY, LINER, Sy, Sy1, Sy1.2,
Sy1.5, Sy1.8, Sy1.9 or Sy2) (1)
81- 85 F5.3 --- z [0.001/0.3] Redshift from Ajello et al.,
2009, Cat. J/ApJ/699/603
87- 90 F4.2 --- Gamma [1.47/3.44] X-ray photon index Γ
92- 95 F4.2 --- E_Gamma Positive error on Gamma
97-100 F4.2 --- e_Gamma Negative error on Gamma
102 A1 --- l_logNH [≳] Limit flag on logNH
103-107 F5.2 [cm-2] logNH ? Absorbing column density (NH)
109-110 I2 --- r_logNH ? Reference (2)
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Note (1): The optical classification comes mainly from Tueller et al. (2008,
Cat. J/ApJ/681/113), Winter et al. (2009ApJ...690.1322W 2009ApJ...690.1322W), Parisi et
al. (2009A&A...507.1345P 2009A&A...507.1345P), Cusumano et al. (2010, Cat. J/A+A/524/A64),
SIMBAD, and NED.
Note (2): References as follows:
1 = Tueller et al. 2008, Cat. J/ApJ/681/113;
2 = This work: follow-up with XRT;
3 = This work: follow-up with XMM;
4 = See Table 3 for a detailed analysis of the Compton-thick sources;
5 = Shinozaki et al. 2006AJ....131.2843S 2006AJ....131.2843S;
6 = Winter et al. 2009ApJ...690.1322W 2009ApJ...690.1322W;
7 = Ueda et al. 2007ApJ...664L..79U 2007ApJ...664L..79U;
8 = Georgantopoulos et al. 2005, Cat. J/MNRAS/360/782;
9 = Winter et al. 2009ApJ...701.1644W 2009ApJ...701.1644W;
10 = Matt et al. 2009A&A...496..653M 2009A&A...496..653M;
11 = Cappi et al. 2006A&A...446..459C 2006A&A...446..459C;
12 = Page et al. 2005MNRAS.364..195P 2005MNRAS.364..195P;
13 = Winter et al. 2008ApJ...674..686W 2008ApJ...674..686W;
14 = Shu et al. 2007ApJ...657..167S 2007ApJ...657..167S;
15 = Jimenez-Bailon et al. 2007A&A...461..917J 2007A&A...461..917J
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 05-Sep-2012