J/ApJ/881/L24 Black hole masses of SDSS Seyfert 1 galaxies (Viswanath+, 2019)
Are narrow-line Seyfert 1 galaxies powered by low-mass black holes?
Viswanath G., Stalin C.S., Rakshit S., Kurian K.S., Ujjwal K.,
Gudennavar S.B., Kartha S.S.
<Astrophys. J., 881, L24-24 (2019)>
=2019ApJ...881L..24V 2019ApJ...881L..24V (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, Seyfert; Redshifts; Spectra, optical; Black holes
Keywords: accretion, accretion disks; galaxies: active; galaxies: Seyfert
Abstract:
Narrow-line Seyfert 1 galaxies (NLS1s) are believed to be powered by
the accretion of matter onto low-mass black holes (BHs) in spiral host
galaxies with BH masses MBH∼106-108M☉. However, the
broadband spectral energy distribution of the γ-ray-emitting
NLS1s are found to be similar to flat-spectrum radio quasars. This
challenges our current notion of NLS1s having low MBH. To resolve
this tension of low MBH values in NLS1s, we fitted the observed
optical spectrum of a sample of radio-loud NLS1s (RL-NLS1s),
radio-quiet NLS1s (RQ-NLS1s), and radio-quiet broad-line Seyfert 1
galaxies (RQ-BLS1s) of ∼500 each with the standard Shakura-Sunyaev
accretion disk (AD) model. For RL-NLS1s we found a mean
log(MBHAD/M☉) of 7.98±0.54. For RQ-NLS1s and RQ-BLS1s we
found mean log(MBHAD/M☉) of 8.00±0.43 and 7.90±0.57,
respectively. While the derived MBHAD values of RQ-BLS1s are
similar to their virial masses, for NLS1s the derived MBHAD values
are about an order of magnitude larger than their virial estimates.
Our analysis thus indicates that NLS1s have MBH similar to RQ-BLS1s
and their available virial MBH values are underestimated, influenced
by their observed relatively small emission line widths. Considering
Eddington ratio as an estimation of the accretion rate and using
MBHAD, we found the mean accretion rate of our RQ-NLS1s, RL-NLS1s,
and RQ-BLS1s as 0.06-0.05+0.16, 0.05-0.04+0.18 and
0.05-0.04+0.15, respectively. Our results therefore suggest that
NLS1s have BH masses and accretion rates that are similar to BLS1s.
Description:
Our sources are drawn from the catalog of narrow-line Seyfert 1
galaxies (NLS1s) by Rakshit+ (2017, J/ApJS/229/39). We
cross-correlated 11101 NLS1s with the Faint Images of the Radio Sky at
Twenty cm (FIRST) survey within a search radius of 2" to find
radio-emitting NLS1s. This led us to a sample of 554 NLS1s detected in
FIRST, which is around 5% of the total sample of NLS1s.
To check for any differences in the derived BH masses of RL-NLS1s,
relative to radio-quiet NLS1s (RQ-NLS1s) and BLS1s, we also selected a
control sample of RQ-NLS1s and radio-quiet BLS1s (RQ-BLS1).
The Shakura-Sunyaev (S&S) accretion disk (AD) model
(Shakura & Sunyaev 1973A&A....24..337S 1973A&A....24..337S) fitting was carried out on
RL-NLS1s, RQ-NLS1s, and RQ-BLS1s, each consisting of 554 sources
(except for RQ-BLS1s, which contain 471 sources). Of these, our
automatic fitting procedure converged for 537 RL and RQ-NLS1s, and
448 RQ-BLS1s.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 87 1522 Results of accretion disk (AD) model fitting
to the SDSS spectra
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See also:
V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
VIII/92 : The FIRST Survey Catalog, Version 2014Dec17 (Helfand+ 2015)
VII/283 : The Million Quasars (Milliquas) catalog (6.3) (Flesch, 2019)
J/A+A/309/81 : X-ray properties of AGN (Wang+, 1996)
J/AJ/124/3042 : Narrow-line Seyfert 1 galaxies from SDSS EDR (Williams+, 2002)
J/ApJS/166/128 : Narrow line Seyfert 1 galaxies from SDSS-DR3 (Zhou+, 2006)
J/ApJS/229/39 : Narrow line Seyfert 1 galaxies from SDSS-DR12 (Rakshit+, 2017)
J/MNRAS/466/3309 : X-ray flux variability of AGN (Rani+, 2017)
J/other/NewA/54.30 : NLS1s 2MASS and WISE photometry (Chen+, 2017)
J/A+A/603/A100 : 37 GHz observations of NLS1 galaxies (Lahteenmaki+, 2017)
J/A+A/615/A13 : Narrow line Seyfert 1 (NLS1) galaxies spectra (Schmidt+, 2018)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh Hour of Right Ascension (J2000)
4- 5 I2 min RAm Minute of Right Ascension (J2000)
7- 11 F5.2 s RAs Second of Right Ascension (J2000)
13 A1 --- DE- Sign of the Declination (J2000)
14- 15 I2 deg DEd Degree of Declination (J2000)
17- 18 I2 arcmin DEm Arcminute of Declination (J2000)
20- 23 F4.1 arcsec DEs Arcsecond of Declination (J2000)
25- 29 F5.3 --- z [0.01/0.8] Spectroscopic redshift
31- 37 A7 --- Type Object type (1)
39- 45 F7.3 [-] logR [-46.2/5.4]? log radio loudness (2)
47- 51 F5.2 [10-7W] logLHb [39.8/44.5] log Hβ luminosity; erg/s
53- 57 F5.2 [-] logMVM [5.2/10.1] log black hole mass
from virial method
59- 62 F4.2 [-] logMAD [6/9.3] log black hole mass
from AD model fit
64- 67 F4.2 [-] E_logMAD [0/1.5] Upper uncertainty in logMAD
69- 72 F4.2 [-] e_logMAD [0.1/1.4] Lower uncertainty in logMAD
74- 77 F4.2 --- lambda-Edd [0/9.9] Accretion rate λEdd (3)
79- 82 F4.2 --- E_lambda-Edd [0/4.7] Upper uncertainty in lambda-Edd
84- 87 F4.2 --- e_lambda-Edd [0/4.2] Lower uncertainty in lambda-Edd
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Note (1): Type as follows:
RL-NLS1 = radio-loud narrow-line Seyfert 1 galaxies (537 occurrences)
RQ-NLS1 = radio-quiet NLS1s (537 occurrences)
RQ-BLS1 = radio-quiet broad-line Seyfert 1 galaxies (448 occurrences)
Note (2): Our sample has an average radio-loudness of logR=1.32, where
R=F(5GHz)/F(B-band), with F(5GHz) and F(B-band) being the flux
densities in the radio band at 5GHz and optical B-band, respectively.
Note (3): Calculated as λEdd=424xL(Hβ)/LEdd for NLS1s and
λEdd=303xL(Hβ)/LEdd for BLS1s,
where LEdd is the Eddington luminosity defined as
LEdd=1.3x1038(MADBH/M☉)erg/s
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 29-Jan-2021