J/MNRAS/487/2463 Hot corona properties of Swift/BAT-detected AGNs (Wang+, 2019)
Hot corona properties of Swift/BAT-detected AGNs.
Wang C., Yu L.-M., Bian W.-H., Zhao B.-X.
<Mon. Not. R. Astron. Soc., 487, 2463-2473 (2019)>
=2019MNRAS.487.2463W 2019MNRAS.487.2463W (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei ; Black holes ; Accretion ; X-ray sources
Keywords: accretion, accretion discs - galaxies: active - magnetic fields
Abstract:
Using a sample of 208 broad-line active galactic nuclei (AGNs) from
the Swift/BAT AGN Spectroscopic Survey in the ultra-hard X-ray band
(14-195keV), the hot corona properties are investigated, i.e. the
fraction of gravitational energy dissipated in the hot corona and the
hard X-ray photon index. The bolometric luminosity, LBol, is
calculated from host-corrected luminosity at 5100Å. Virial
supermassive black-hole masses (SMBH, MBH) are calculated from the
Hβ line width and the corresponding broad-line region
size-luminosity empirical relation at 5100Å. We find a strong
anti-correlation between the fraction of energy released in corona
(FX=L14-195keV/LBol) and the Eddington ratio
(ε=LBol/LEdd), FX∝ε-0.60±0.1. It is
found that this fraction also has a correlation with the SMBH mass,
FX∝ε-0.74±0.14MBH-0.30±0.03. Assuming that
magnetic buoyancy and field reconnection lead to the formation of a
hot corona, our result favours the shear stress tensor being a
proportion of the gas pressure. For our entire sample, it is found
that the hard X-ray photon index Γ has a weak but significant
correlation with the Eddington ratio, Γ=2.17+0.21logε.
However, this correlation is not robust because the relation is not
statistically significant for its subsample of 32
reverberation-mapping AGNs with relatively reliable MBH or its
subsample of 166 AGNs with single-epoch MBH. We do not find a
statistically significant relation between the photon index and the
Eddington ratio taking into account an additional dependence on FX.
Description:
The sample of AGNs used here is selected from Swift BASS drawn from a
Swift/BAT 70-month catalogue (Koss et al. 2017ApJ...850...74K 2017ApJ...850...74K, Cat.
J/ApJ/850/74). The Swift/BAT survey has an all-sky survey in the
ultra-hard X-ray band (14-195keV) which increases the all-sky
sensitivity by a factor of 20 compared to previous satellites. Most of
the Swift/BAT-detected AGNs are nearby (z<0.05); these bright and
nearby AGNs offer the best opportunity for studies of corona
properties of AGNs with information at the ultra-hard X-ray band.
There are 227 Swift/BAT-detected broad-line AGNs with measured broad
Hβ full-width at half-maximum (FWHM) and the luminosity at
5100Å. Excluding 19 beamed sources (Koss et al.
2017ApJ...850...74K 2017ApJ...850...74K, Cat. J/ApJ/850/74), our sample is finally
composed of 208 Swift/BAT-detected broad-line AGNs.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 46 208 A sample of 208 broad-line AGNs detected by
Swift/BAT
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See also:
J/ApJ/850/74 : Swift/BAT AGN Spectroscopic Survey. I. (Koss+, 2017)
J/ApJS/233/17 : Swift/BAT AGN spectroscopic survey. V. X-ray data
(Ricci+, 2017)
J/ApJ/818/L14 : RM AGNs accretion rates and BH masses (Du+, 2016)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- ID Swift/BAT 70-month hard X-ray survey ID (1)
6- 10 F5.2 [10-7W] logLx Logarithm of hard X-ray luminosity
(14-195keV) (1)
12- 16 F5.2 [10-7W] logL5100 Logarithm of host-corrected 5100Å
luminosity
18- 22 F5.2 [10-7W] logLbol Logarithm of the bolometric luminosity (2)
24- 27 F4.2 [Msun] logMBH Logarithm of the black-hole mass
29- 32 F4.2 --- Gamma ? Photon index of the primary X-ray continuum
recovered from the entire energy range
(0.3-150keV) and the full multi-component
model (3)
34- 37 F4.2 --- E_Gamma ? Upper error on Gamma
39- 42 F4.2 --- e_Gamma ? Lower error on Gamma
44 A1 --- r_logL5100 [DK] References for logL5100 (4)
46 A1 --- r_logMBH [0/2] References for logMBH (5)
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Note (1): IDs and logLx are from Table 2 in Koss et al. (2017ApJ...850...74K 2017ApJ...850...74K,
Cat. J/ApJ/850/74/agns)
Note (2): Using the host-corrected luminosity L5100, we calculate the
bolometric luminosity Lbol through the bolometric correction factor
at 5100Å (Marconi et al. 2004MNRAS.351..169M 2004MNRAS.351..169M):
log(Lbol/L5100)=0.837-0.067l+0.017l2-0.0023l3, where l=logLbol-12
Note (3): Photon index adopted from Ricci et al. (2017ApJS..233...17R 2017ApJS..233...17R,
Cat. J/ApJS/233/17)
Note (4): References as follows:
D = Monochromatic luminosity at 5100Å in the rest frame from
Du et al. (2016ApJ...818L..14D 2016ApJ...818L..14D, Cat. J/ApJ/818/L14)
K = Monochromatic luminosity at 5100Å in the rest frame from Table 9 in
Koss et al. (2017ApJ...850...74K 2017ApJ...850...74K, Cat. J/ApJ/850/74/table9)
Note (5): References as follows:
0 = Black-hole mass MBH from Du et al. (2016ApJ...818L..14D 2016ApJ...818L..14D,
Cat. J/ApJ/818/L14)
1 = Black-hole mass MBH from the MBH-σ* relation with measured
σ* (Kormendy & Ho 2013ARA&A..51..511K 2013ARA&A..51..511K; Koss et al.
2017ApJ...850...74K 2017ApJ...850...74K, Cat. J/ApJ/850/74)
2 = Black-hole mass MBH from the single-epoch spectrum in this work
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 15-Nov-2022