Revisiting the Fraction of Radio-Loud Narrow Line Seyfert 1 Galaxies with LoTSS DR1

Radio-Loud narrow-line Seyfert 1 galaxies (NLS1s), especially the extremely radio-loud ones, are widely accepted as the jetted versions of NLS1s. We explore the radio-loud fraction for NLS1s with recently released LoTSS DR1 at 150 MHz. The radio detection rate is about 28% for LoTSS DR1. The radio detected NLS1s have lower redshift than the non-detected ones. Moreover, the 150 MHz radio luminosities of NLS1s detected by LoTSS are about two orders of magnitude weaker than those of the previous samples. By defining the radio loudness with the ratio between 150 MHz radio flux and SDSS r band flux, the radio-loud fraction is about 1% with the critical radio loudness equalling 100. Radio loudness shows no dependence on central black hole mass, while weak correlations are found between radio loudness and disk luminosity, as well as Eddington ratio.

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ASCA Observations of Narrow-Line Seyfert 1 Galaxies

International Astronomical Union Colloquium ◽

10.1017/s0252921100039592 ◽

1997 ◽

Vol 159 ◽

pp. 40-43 ◽

Cited By ~ 2

Author(s):

K. Hayashida

Keyword(s):

Black Hole ◽

Narrow Line ◽

Black Hole Mass ◽

Central Black Hole ◽

X Ray ◽

Eddington Limit

AbstractASCA observations of four narrow-line Seyfert 1 galaxies are presented. Among the four sources, two show X-ray spectra consisting of soft and hard components. Rapid X-ray variability is observed in all four sources. We estimate the central black-hole mass of these sources and find indications that the apparent luminosities exceed the Eddington limit under some assumptions.

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Probing narrow-line Seyfert 1 galaxies in the southern hemisphere

Astronomy and Astrophysics ◽

10.1051/0004-6361/201832678 ◽

2018 ◽

Vol 615 ◽

pp. A167 ◽

Cited By ~ 9

Author(s):

S. Chen ◽

M. Berton ◽

G. La Mura ◽

E. Congiu ◽

V. Cracco ◽

...

Keyword(s):

Black Hole ◽

Southern Hemisphere ◽

Narrow Line ◽

Strong Correlations ◽

Black Hole Mass ◽

Central Black Hole ◽

Massive Black Hole ◽

Final Data ◽

First Time ◽

Field Galaxy

We present a new accurate catalog of narrow-line Seyfert 1 galaxies (NLS1s) in the southern hemisphere from the Six-degree Field Galaxy Survey (6dFGS) final data release, which is currently the most extensive spectroscopic survey available in the southern sky whose database has not yet been systematically explored. We classified 167 sources as NLS1s based on their optical spectral properties. We derived flux-calibrated spectra for the first time that the 6dFGS does not provide. By analyzing these spectra, we obtained strong correlations between the monochromatic luminosity at 5100 Å and the luminosities of Hβ and [O III]λ5007 lines. The central black hole mass and the Eddington ratio have average values of 8.6 × 106M⊙ and 0.96 LEdd respectively, which are typical values for NLS1s. In the sample, 23 (13.8%) NLS1s were detected at radio frequencies, and 12 (7.0%) of them are radio-loud. Our results confirmed that radio-loud sources tend to have higher redshift, a more massive black hole, and higher radio and optical luminosities than radio-quiet sources.

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Black hole demographics from TDE modeling

Proceedings of the International Astronomical Union ◽

10.1017/s1743921318007305 ◽

2018 ◽

Vol 14 (S342) ◽

pp. 260-262

Author(s):

T. Mageshwaran ◽

A. Mangalam

Keyword(s):

Black Hole ◽

Detection Rate ◽

Capture Rate ◽

Cosmological Parameters ◽

Mass Function ◽

Black Hole Mass ◽

Statistical Average ◽

Central Black Hole ◽

Tidal Disruption ◽

Accretion Model

AbstractThe occurence rate of tidal disruption events (TDEs) by survey missions depend on the black hole mass function of the galaxies, properties of the stellar cusp and mass of the central black hole. Using a power law density profile with Kroupa mass function, we solve the steady state Fokker-Planck to calculate the theoretical capture rate of stars by the black hole. Using a steady accretion model, the Schechter black hole mass function (BHMF) and the cosmological parameters, we calculate the detection rate of TDEs for various surveys which is then fit with the observed TDE rates to extract the Schechter parameters. The rate tension between observation (∼10−5yr−1) and theory (∼10−4yr−1 for individual galaxies is explained by the statistical average over the BHMF.

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Wandering of the central black hole in a galactic nucleus and correlation of the black hole mass with the bulge mass

Publications of the Astronomical Society of Japan ◽

10.1093/pasj/psab009 ◽

2021 ◽

Author(s):

Hajime Inoue

Keyword(s):

Black Hole ◽

Loss Rate ◽

Energy Gain ◽

Stellar Disk ◽

Black Hole Mass ◽

Central Black Hole ◽

Massive Black Hole ◽

Stellar Cluster ◽

Upper Limit ◽

Simple Parameter

Abstract We investigate a mechanism for a super-massive black hole at the center of a galaxy to wander in the nucleus region. A situation is supposed in which the central black hole tends to move by the gravitational attractions from the nearby molecular clouds in a nuclear bulge but is braked via the dynamical frictions from the ambient stars there. We estimate the approximate kinetic energy of the black hole in an equilibrium between the energy gain rate through the gravitational attractions and the energy loss rate through the dynamical frictions in a nuclear bulge composed of a nuclear stellar disk and a nuclear stellar cluster as observed from our Galaxy. The wandering distance of the black hole in the gravitational potential of the nuclear bulge is evaluated to get as large as several 10 pc, when the black hole mass is relatively small. The distance, however, shrinks as the black hole mass increases, and the equilibrium solution between the energy gain and loss disappears when the black hole mass exceeds an upper limit. As a result, we can expect the following scenario for the evolution of the black hole mass: When the black hole mass is smaller than the upper limit, mass accretion of the interstellar matter in the circumnuclear region, causing the AGN activities, makes the black hole mass larger. However, when the mass gets to the upper limit, the black hole loses the balancing force against the dynamical friction and starts spiraling downward to the gravity center. From simple parameter scaling, the upper mass limit of the black hole is found to be proportional to the bulge mass, and this could explain the observed correlation of the black hole mass with the bulge mass.

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Observations of the γ-ray emitting narrow-line Seyfert 1, SBS 0846+513, and its host galaxy

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab1046 ◽

2021 ◽

Author(s):

Timothy S Hamilton ◽

Marco Berton ◽

Sonia Antón ◽

Lorenzo Busoni ◽

Alessandro Caccianiga ◽

...

Keyword(s):

Black Hole ◽

Adaptive Optics ◽

Host Galaxy ◽

Narrow Line ◽

Black Hole Mass ◽

Residual Structure ◽

Line Region ◽

Resolution Imaging ◽

Γ Ray ◽

Adaptive Optics System

Abstract The γ-ray emitting galaxy SBS 0846 + 513 has been classified as a Narrow-Line Seyfert 1 (NLS1) from its spectroscopy, and on that basis would be thought likely to have a small central black hole hosted in a spiral galaxy. But very few of the γ-ray NLS1 have high-resolution imaging of their hosts, so it is unknown how the morphology expectation holds up for the γ-emitting class. We have observed this galaxy in the J-band with the Large Binocular Telescope’s LUCI1 camera and the ARGOS adaptive optics system. We estimate its black hole mass to lie between $4.2\times 10^7 \le \frac{\text{M}}{\text{M}_\odot } \le 9.7\times 10^7$, using the correlation with bulge luminosity, or $1.9\times 10^7 \le \frac{\text{M}}{\text{M}_\odot } \le 2.4\times 10^7$ using the correlation with Sérsic index. Our favoured estimate is 4.2 × 107M⊙, putting its mass at the high end of the NLS1 range in general but consistent with others that are γ-ray emitters. These estimates are independent of the Broad Line Region viewing geometry and avoid any underestimates due to looking down the jet axis. Its host shows evidence of a bulge + disc structure, from the isophote shape and residual structure in the nuclear-subtracted image. This supports the idea that γ-ray NLS1 may be spiral galaxies, like their non-jetted counterparts.

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