A spectroscopic analysis of a sample of narrow-line Seyfert 1 galaxies selected from the Sloan Digital Sky Survey

Cracco, V.; Ciroi, S.; Berton, M.; Mille, F. Di; Foschini, L.; Mura, G. La; Rafanelli, P.

doi:10.1093/mnras/stw1689

Cited by 88 publications

(141 citation statements)

References 126 publications

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“…The nature of this anticorrelation thus still requires a more detailed physical explanation. Our results are complementary to the recent study of Cracco et al (2016). They analyzed a large sample of NLS1 galaxies and confirmed the generally Lorentzian shape of their Balmer lines but also considerable overlap in the properties with Seyfert 1 galaxies.…”

Section: Discussionsupporting

confidence: 83%

Properties of active galaxies at the extreme of Eigenvector 1

Śniegowska

You

Panda

et al. 2018

A&A

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Context. Eigenvector 1 (EV1) is the formal parameter which allows the introduction of some order in the properties of the unobscured type 1 active galaxies. Aims. We aim to understand the nature of this parameter by analyzing the most extreme examples of quasars with the highest possible values of the corresponding eigenvalues R Fe . Methods. We selected the appropriate sources from the Sloan Digital Sky Survey (SDSS) and performed detailed modeling, including various templates for the Fe II pseudo-continuum and the starlight contribution to the spectrum. Results. Out of 27 sources with R Fe larger than 1.3 and with the measurement errors smaller than 20% selected from the SDSS quasar catalog, only six sources were confirmed to have a high value of R Fe , defined as being above 1.3. All other sources have anR Fe of approximately 1. Three of the high R Fe objects have a very narrow Hβ line, below 2100 km s −1 but three sources have broad lines, above 4500 km s −1 , that do not seem to form a uniform group, differing considerably in black hole mass and Eddington ratio; they simply have a very similar EW([OIII]5007) line. Therefore, the interpretation of the EV1 remains an open issue.

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Section: Discussionsupporting

confidence: 83%

Properties of active galaxies at the extreme of Eigenvector 1

Śniegowska

You

Panda

et al. 2018

A&A

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“…Wind model predicts appreciable blueshift excess in the line profiles (see Waters et al and the references therein) while Narrow Line Seyfert 1 galaxies show symmetric lines, well modeled with a single Lorentzian shape (e.g. Laor et al 1987;Cracco et al 2016). Some Broad Line Seyfert 1 galaxies and quasars show an additional, separate, blueshifted component (see e.g.…”

Section: Introductionmentioning

confidence: 96%

A Test of the Formation Mechanism of the Broad Line Region in Active Galactic Nuclei

Czerny

Wang

et al. 2016

ApJ

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The origin of the Broad Line Region (BLR) in active galaxies remains unknown. It seems to be related to the underlying accretion disk but an efficient mechanism is required to rise the material from the disk surface without giving too strong signatures of the outflow in the case of the low ionization lines. We discuss in detail two proposed mechanisms: (i) radiation pressure acting on dust in the disk atmosphere creating a failed wind (ii) the gravitational instability of the underlying disk. We compare the predicted location of the inner radius of the BLR in those two scenarios with the observed position obtained from the reverberation studies of several active galaxies. The failed dusty outflow model well represents the observational data while the predictions of the self-gravitational instability are not consistent with observations. The issue remains why actually we do not see any imprints of the underlying disk instability in the BLR properties.

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“…Radio-quiet 1 NLS1s (RQNLS1s) constitute 93% of the total population up to redshift 0.8 (Komossa et al 2006) and 96.5% at z < 0.35 (Cracco et al 2016). Radio-loud NLS1s (RLNLS1s) are relatively uncommon.…”

Section: Introductionmentioning

confidence: 99%

Kiloparsec-scale emission in the narrow-line Seyfert 1 galaxy Mrk 783

Congiu

Berton

Giroletti

et al. 2017

A&A

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We present the first results of a radio survey of 79 narrow-line Seyfert 1 (NLS1) carried out with the Karl G. Jansky Very Large Array (JVLA) at 5 GHz in A configuration aimed at studying the radio properties of these sources. We report the detection of extended emission in one object: Mrk 783. This is intriguing, since the radio-loudness parameter R of this object is close to the threshold between radio-quiet and radio-loud active galactic nuclei (AGN). The galaxy is one of the few NLS1 showing such an extended emission at z < 0.1. The radio emission is divided into a compact core component and an extended component, observed on both sides of the nucleus and extending from 14 kpc southeast to 12 kpc northwest. There is no sign of a collimated jet and the shape of the extended component is similar to those of some Seyfert galaxies. The properties of the emission are compatible with a relic produced by the intermittent activity cycle of the AGN.

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A spectroscopic analysis of a sample of narrow-line Seyfert 1 galaxies selected from the Sloan Digital Sky Survey

Cited by 88 publications

References 126 publications

Properties of active galaxies at the extreme of Eigenvector 1

Properties of active galaxies at the extreme of Eigenvector 1

A Test of the Formation Mechanism of the Broad Line Region in Active Galactic Nuclei

Kiloparsec-scale emission in the narrow-line Seyfert 1 galaxy Mrk 783

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