Radiation mechanisms and physical properties of the γ-ray narrow-line Seyfert 1 galaxies

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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Independent Estimation of Black Hole Mass for the γ-ray-detected Archetypal Narrow-line Seyfert 1 Galaxy 1H 0323+342 from X-Ray Variability

The Astrophysical Journal ◽

10.3847/1538-4357/aadd4a ◽

2018 ◽

Vol 866 (1) ◽

pp. 69 ◽

Cited By ~ 7

Author(s):

Hai-Wu Pan ◽

Weimin Yuan ◽

Su Yao ◽

S. Komossa ◽

Chichuan Jin

Keyword(s):

Black Hole ◽

Narrow Line ◽

Black Hole Mass ◽

X Ray ◽

Γ Ray

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Physical Properties of Molecular Envelopes in Low-Mass Star-Forming Regions

Symposium - International Astronomical Union ◽

10.1017/s007418090016468x ◽

2000 ◽

Vol 197 ◽

pp. 61-70

Author(s):

Nagayoshi Ohashi

Keyword(s):

Physical Properties ◽

Young Stellar Objects ◽

Mass Star ◽

Narrow Line ◽

Stellar Objects ◽

Velocity Pattern ◽

Star Forming ◽

Star Forming Regions ◽

Low Mass ◽

Line Widths

We have carried out interferometric observations of pre-protostellar and protostellar envelopes in Taurus. Protostellar envelopes are dense gaseous condensations with young stellar objects or protostars, while pre-protostellar envelopes are those without any known young stellar objects. Five pre-protostellar envelopes have been observed in CCS JN=32–21, showing flattened and clumpy structures of the envelopes. The observed CCS spectra show moderately narrow line widths, ~0.1 to ~0.35 km s–1. One pre-protostellar envelope, L1544, shows a remarkable velocity pattern, which can be explained in terms of infall and rotation. Our C18O J=1–0 observations of 8 protostellar envelopes show that they have also flattened structures like pre-protostellar envelopes but no clumpy structures. Four out the eight envelopes show velocity patterns that can be explained by motions of infall (and rotation). Physical properties of pre-protostellar and protostellar envelopes are discussed in detail.

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The relativistic jet of the γ-ray emitting narrow-line Seyfert 1 galaxy PKS J1222+0413

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz1193 ◽

2019 ◽

Vol 487 (1) ◽

pp. 181-197 ◽

Cited By ~ 4

Author(s):

Daniel Kynoch ◽

Hermine Landt ◽

Martin J Ward ◽

Chris Done ◽

Catherine Boisson ◽

...

Keyword(s):

Near Infrared ◽

Uv Spectroscopy ◽

Spectral Energy Distribution ◽

Broad Band ◽

Physical Models ◽

Spectral Energy ◽

Narrow Line ◽

Relativistic Jet ◽

Γ Ray ◽

Apply Physical

ABSTRACT We present a multifrequency study of PKS J1222+0413 (4C +04.42), currently the highest redshift γ-ray emitting narrow-line Seyfert 1 (γ-NLS1). We assemble a broad spectral energy distribution (SED) including previously unpublished datasets: X-ray data obtained with the NuSTAR and Neil Gehrels Swift observatories; near-infrared, optical, and UV spectroscopy obtained with VLT X-shooter; and multiband radio data from the Effelsberg telescope. These new observations are supplemented by archival data from the literature. We apply physical models to the broad-band SED, parametrizing the accretion flow and jet emission to investigate the disc–jet connection. PKS J1222+0413 has a much greater black hole mass than most other NLS1s, MBH ≈ 2 × 108 M$\odot$, similar to those found in flat spectrum radio quasars (FSRQs). Therefore this source provides insight into how the jets of γ-NLS1s relate to those of FSRQs.

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Gamma-ray-emitting narrow-line Seyfert 1 galaxies: the Swift view

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1580 ◽

2020 ◽

Vol 496 (2) ◽

pp. 2213-2229 ◽

Cited By ~ 1

Author(s):

F D’Ammando

Keyword(s):

Gamma Ray ◽

Thermal Emission ◽

Optical Emission ◽

X Rays ◽

Narrow Line ◽

X Ray ◽

Relativistic Jet ◽

Photon Index ◽

Γ Ray ◽

Lower Variability

ABSTRACT We report the analysis of all Swift observations available up to 2019 April of γ-ray-emitting narrow-line Seyfert 1 galaxies (NLSy1). The distribution of X-ray luminosities (and fluxes) indicates that the jet radiation significantly contributes to their X-ray emission, with Doppler boosting making values higher than other radio-loud NLSy1. The 0.3–10 keV photon indices are on average harder with respect to radio-quiet and radio-loud NLSy1, confirming a dominant jet contribution in X-rays. However, the lower variability amplitude with respect to blazars and the softening of the spectrum in some periods suggests that also the corona radiation contributes to the X-ray emission. In optical and ultraviolet (UV) significant flux changes have been observed on daily, weekly, and monthly time-scale, providing a clear indication of the significant contribution of the jet radiation in this part of spectrum. A strong correlation between X-ray, UV, and optical emission and simultaneous flux variations have been observed in 1H 0323+342, SBS 0846+513, PMN J0948+0022 as expected in case the jet radiation is the dominant mechanism. Correlated multiband variability favours the jet-dominated scenario also in FBQS J1644+2619 and PKS 2004−447. The summed X-ray Telescope spectra of 1H 0323+342, SBS 0846+513, PMN J0948+0022, and FBQS J1644+2619 are well fitted by a broken power law with a break around 2 keV. The spectrum above 2 keV is dominated by the non-thermal emission from a beamed relativistic jet, as suggested by the hard photon index. A Seyfert-like feature like the soft X-ray excess has been observed below 2 keV, making these γ-ray-emitting NLSy1 different from typical blazars.

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