J/ApJ/763/111 X-ray spectral analysis of Swift/BAT AGNs (Vasudevan+, 2013)
X-ray properties of the northern Galactic cap sources in the 58 month
Swift/BAT catalog.
Vasudevan R.V., Brandt W.N., Mushotzky R.F., Winter L.M., Baumgartner W.H.,
Shimizu T.T., Schneider D.P., Nousek J.
<Astrophys. J., 763, 111 (2013)>
=2013ApJ...763..111V 2013ApJ...763..111V
ADC_Keywords: Active gal. nuclei ; X-ray sources ; Surveys ; Redshifts
Keywords: galaxies: active; surveys; X-rays: galaxies
Abstract:
We present a detailed X-ray spectral analysis of the non-beamed, hard
X-ray selected active galactic nuclei (AGNs) in the northern Galactic
cap of the 58 month Swift Burst Alert Telescope (Swift/BAT) catalog,
consisting of 100 AGNs with b>50°. This sky area has excellent
potential for further dedicated study due to a wide range of
multi-wavelength data that are already available, and we propose it as
a low-redshift analog to the "deep field" observations of AGNs at
higher redshifts (e.g., CDFN/S, COSMOS, Lockman Hole). We present
distributions of luminosity, absorbing column density, and other key
quantities for the catalog. We use a consistent approach to fit new
and archival X-ray data gathered from XMM-Newton, Swift/XRT, ASCA, and
Swift/BAT. We probe to deeper redshifts than the 9 month BAT catalog
(=0.043 compared to =0.03 for the 9 month catalog), and uncover
a broader absorbing column density distribution. The fraction of
obscured (logNH≥22) objects in the sample is ∼60%, and 43%-56% of
the sample exhibits "complex" 0.4-10keV spectra. We present the
average 1-10keV spectrum for the sample, which reproduces the 1-10keV
X-ray background slope as found for the brighter 9 month BAT AGN
sample.
Description:
106 sources consist of Seyferts (Type 1 and 2 and intermediate types),
quasars/AGN, LINERs, and the more general category of galaxies,
including two "X-ray Bright Optically Normal Galaxies" (XBONGs) are
selected from the 58 month BAT catalog
(http://swift.gsfc.nasa.gov/results/bs58mon/).
We use the XMM-Newton X-ray Science Archive (XSA) to download all the
available XMM-Newton data for the 106 sources, and find that 49 of
these objects have XMM-Newton spectra (including the new observations
from the XMM-Newton proposal). We therefore provide as complete an
analysis as possible for the 49 AGN candidates with XMM-Newton data,
and turn to the Swift X-ray Telescope (XRT) and ASCA archives to
provide basic coverage for the remaining sources. The final list
contains 100 objects for which we have obtained data from XMM-Newton,
XRT, or ASCA.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 141 100 Table of observations used for each object
table3.dat 163 108 Basic fit results for 95 AGNs
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See also:
B/xmm : XMM-Newton Observation Log (XMM-Newton Science Operation Center, 2012)
VI/117 : Observation Log from ASCA (PLAIN Center, 2001)
J/ApJS/207/19 : Swift-BAT 2004-2010 hard X-ray survey (Baumgartner+, 2013)
J/ApJ/754/45 : IR properties of Swift/BAT X-ray AGNs (Ichikawa+, 2012)
J/ApJ/753/104 : AGN identifications from AKARI and Swift (Matsuta+, 2012)
J/ApJ/749/21 : AGNs detected by 60 month Swift/BAT survey (Ajello+, 2012)
J/A+A/530/A42 : X-ray properties of AGNs in XBS (Corral+, 2011)
J/A+A/529/A135 : AGN Opt/IR properties in Lockman Hole (Rovilos+, 2011)
J/ApJ/739/57 : Ultra hard X-ray AGNs in the Swift/BAT survey (Koss+, 2011)
J/ApJ/728/58 : Swift-BAT survey of AGNs (Burlon+, 2011)
J/MNRAS/413/1206 : XMM survey of 12um selected galaxies (Brightman+, 2011)
J/ApJS/186/378 : Hard X-ray survey from Swift-BAT 2004-2006 (Tueller+, 2010)
J/A+A/510/A48 : Palermo Swift-BAT Hard X-ray Catalogue (Cusumano+, 2010)
J/A+A/505/417 : Second INTEGRAL AGN catalogue (Beckmann+, 2009)
J/ApJ/699/603 : Evolution of Swift/BAT blazars (Ajello+, 2009)
J/ApJ/681/113 : Swift BAT survey of AGNs (Tueller+, 2008)
J/ApJ/678/102 : BAT X-ray survey. I. (Ajello+, 2008)
J/ApJ/633/L77 : SWIFT/BAT detections of AGN (Markwardt+, 2005)
J/AJ/126/2237 : Radio-excess IR galaxies PMN/FSC sample (Drake+, 2003)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 24 A24 --- Name AGN name
25 A1 --- n_Name [n] n: new observation
27- 32 F6.4 --- z [0.001/0.2] AGN redshift
34- 40 F7.3 deg RAdeg Right ascension in decimal degrees (J2000) (1)
42- 48 F7.3 deg DEdeg Declination in decimal degrees (J2000) (1)
50- 56 F7.3 deg GLON Galactic longitude
58- 63 F6.3 deg GLAT [50.2/82.3] Galactic latitude
65- 68 A4 --- Inst Instrument (ASCA, XMM, XRT)
70- 80 I11 --- ObsID Observation identification number
82- 91 A10 "YYYY/MM/DD" Date Observation date (UT)
93- 99 I7 ct Cts [3/1875711] Total number of counts in the
source region at energies 0.4-10keV (2)
101-104 F4.1 ks Time [0.3/96] Observation time
105 A1 --- f_Time [*] *: pile-up correction (3)
107-109 I3 % Use [0/100]? Usable % of obs. (4)
111-127 A17 --- Type Optical type
129-134 F6.2 fW/m2 Fgam [4.3/533.1] BAT flux (14-195keV),
in units of 10-12erg/s/cm2
136-141 F6.2 --- SNR [4.8/275] Signal-to-noise ratio of the BAT
detection
--------------------------------------------------------------------------------
Note (1): The positions quoted are for the identified soft X-ray
(0.4-10keV) counterpart to the BAT source.
Note (2): In all detectors used for fitting, i.e., PN+MOS1+MOS2 for
XMM-Newton.
Note (3): Asterisks indicate that pile-up was corrected for these
XMM-Newton sources.
Note (4): For XMM-Newton observations, corrections for flaring required
excising part of the observation; this was not done for ASCA or XRT
observations where the whole observations were used, and this "Use"
column therefore only applies to XMM-Newton data sets.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 24 A24 --- Name AGN name
26- 31 A6 --- Model Best fitting model (1)
33- 40 F8.2 --- chi2 [3.2/11118] Model χ2
42- 45 I4 --- dof [5/2780] Number of degrees of freedom
47- 51 F5.3 --- Prob [0/1] null-hypothesis probability
53- 56 F4.2 10+20/cm2 NHg [0.6/4.1] Galactic neutral hydrogen column
density
58 A1 --- l_NH Limit flag on NH
60- 64 F5.2 10+20/cm2 NH [19.9/25.4]? Intrinsic column density
(NH) (2)
66- 69 F4.2 10+20/cm2 E_NH [0/1]? Positive uncertainty on NH
71- 74 F4.2 10+20/cm2 e_NH [0/2]? Negative uncertainty on NH
76- 79 F4.2 --- CF [0.1/1]? Covering fraction if
partial-covering model is used
80 A1 --- f_CF [*] *: the covering fraction was poorly
constrained
82- 85 F4.2 --- E_CF [0/0.9]? Positive error on CF (3)
87- 90 F4.2 --- e_CF [0/1]? Negative error on CF (3)
92- 95 F4.2 --- Gamma [1.5/2.2] Photon index Γ (4)
96 A1 --- f_Gamma [*] *: Γ was frozen in the fit
98-101 F4.2 --- E_Gamma [0/0.7]? Positive uncertainty on Gamma
103-106 F4.2 --- e_Gamma [0/1.8]? Negative uncertainty on Gamma
108-113 F6.2 10-16W/m2 F0.5-2 [0/256.5] 0.5-2keV flux
in units of 10-13erg/s/cm2
115-120 F6.2 10-16W/m2 F2-10 [5/668.5] 2-10keV flux in units of
10-13erg/s/cm2
122-126 F5.2 [10-7W] L0.5-2 [39.9/44.7] Absorption-corrected 0.5-2keV
luminosity (log erg/s)
128-132 F5.2 [10-7W] L2-10 [40.3/44.7] Absorption-corrected 2-10keV
luminosity (log erg/s)
134-137 F4.2 [10-7W] E_L2-10 [0/0.9] Positive uncertainty on L2-10
139-143 F5.2 [10-7W] e_L2-10 [0/44.44] Negative uncertainty on L2-10
145-148 F4.1 [10-7W] Lgam [40.8/45]? Swift/BAT 14-195keV luminosity
150-153 F4.1 [10-7W] Lgam2 ? Second value of 14-195keV luminosity
154 A1 --- f_Lgam2 [d] Unexplained † flag on Lgam
156 A1 --- l_RL Limit flag on RL
158-163 F6.3 --- RL [-6/-2.5] Logarithm of radio-loudness (5)
--------------------------------------------------------------------------------
Note (1): Model combination used (see table 2):
-----------------------------------------------------------------------------
Model Description
-----------------------------------------------------------------------------
Simple power-law models
-----------------------------------------------------------------------------
S1 Power-law with Galactic absorption only
S2 Absorbed power-law with Galactic and intrinsic (neutral) absorption
S3 As for S2, with a Fe Kα line at (default) 6.4keV
S4 As for S2, with a soft excess modeled as a blackbody
S5 As for S2, with an edge at 0.73keV (default) to model a warm absorber
S6 As for S2, with both a soft excess and Fe Kα line
S7 Absorbed power-law with warm-absorber edge and Fe Kα line
S8 Absorbed power-law with warm-absorber edge, Fe Kα line and soft
excess
S9 Absorbed power-law with two warm-absorber edges at 0.73 and 0.87keV
(default energies)
S10 Absorbed power-law with two warm-absorber edges and a Fe Kα line
S11 Absorbed power-law with two warm-absorber edges, Fe Kα line and
soft excess
-----------------------------------------------------------------------------
Complex models (partial covering)
-----------------------------------------------------------------------------
C1 Partially covered absorbed power-law with Galactic absorption
C2 As for C1, including a Fe Kα line at (default) 6.4keV
-----------------------------------------------------------------------------
Note (2): blank values indicates an insignificant column density
(below 1019/cm2)
Note (3): Errors below 5x10-3 are not shown.
Note (4): Limits of 1.5<Γ<2.2 were imposed on the fit on physical grounds
Note (5): Logarithm of radio-loudness parameter derived using 5GHz fluxes
or upper limits from the FIRST survey and 2-10keV intrinsic luminosities,
with RL as defined in Terashima & Wilson (2003ApJ...583..145T 2003ApJ...583..145T):
RL=νLν(5GHz)/LX(2-10keV)
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 20-Oct-2014