Photometric Studies of the Seyfert Galaxies NGC 3516, NGC 5548, NGC 3227, NGC 4051, NGC 4151, and NGC 7469

Shomshekova, S. A.; Denissyuk, E. K.; Валиуллин, Р. Р.; Reva, I.; Kusakin, A.

doi:10.1007/s10511-019-09571-w

Cited by 5 publications

(2 citation statements)

References 17 publications

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“…Photometric data for more than 20 Seyfert galaxies were obtained in FAI during the last 10-12 years Shomshekova et al (2019). The light curves of the galaxy NGC 4151, obtained last years are presented in Fig.…”

Section: Results Of Photometric Observationsmentioning

confidence: 99%

Studies of Seyfert galaxies in Fesenkov Astrophysical Institute

Denissyuk

Валиуллин

Omarov

et al. 2020

ComBAO

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This article provides an overview of the main research results of a large group of Seyfert galaxies, carried out at Fesenkov Astrophysical Institute (FAI) over the past 50 years. Spectral observations have been performed since 1970. At an early stage, a three cascade image-tube (UM-92) was used as a radiation receiver. In the 1990s, the equipment was modernized, and at present, the modern CCD cameras are used as radiation detectors at the output of spectrographs. The results of observations were used to determine the absolute fluxes of the emission lines and to study their profiles. Several additional emission features were detected on the wings of the broad emission lines Hα in the spectra of two galaxies NGC 4151 and Ark 120. These features are emitted by compact ionized objects, rotating in the field of Central Body (CB). Photometric observations of Seyfert galaxies have been carried out at FAI since 2010. Light curves of more than 20 Seyfert galaxies have been obtained. In particular, the light curves of the galaxy NGC 4151, obtained last years, shows that an active stage of its nucleus took place in 2015-2016, when the brightness increased by 0m.5 in the V filter, and by almost 2m in the R filter. Then, in 2018-2019 there was a rather sharp decline of brightness, and B V R magnitudes returned to their minimal values.

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Section: Results Of Photometric Observationsmentioning

confidence: 99%

Studies of Seyfert galaxies in Fesenkov Astrophysical Institute

Denissyuk

Валиуллин

Omarov

et al. 2020

ComBAO

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“…Optical photometry of NGC 4151 was taken from Lyuty and Doroshenko (1999); Doroshenko et al (2001); Lyuty (2005); Sergeev et al (2005); Roberts & Rumstay (2012); Oknyansky et al (2013) 1 ; Koshida et al (2014) 2 ; Oknyansky et al (2018); Shomshekova et al (2019).…”

Section: Light Curve Constructionmentioning

confidence: 99%

The Dusty Heart of NGC 4151 Revealed by $λ\sim$1-40 $μ$m Reverberation Mapping and Variability: A Challenge to Current Clumpy Torus Models

Lyu,

Rieke

2020

Preprint

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We probe the dusty environment of the archetypical type-1 AGN in NGC 4151 with comprehensive IR reverberation mapping over several decades, in J (∼ 1.22 µm), H (∼ 1.63 µm), K (∼ 2.19 µm), L (∼ 3.45 µm) and N-band (∼ 10.6 µm), plus multiple measurements at 20-40 µm. At 1-4 µm, the hot dust reverberation signals come from two distinct dust populations at separate radii (∼40 light days and ∼90 light days), with temperatures of ∼1500-2500 K and ∼900-1000 K, consistent with the expected properties of sublimating graphite and silicate dust grains. The torus inner edge defined by the hottest dust remains at roughly the same radius independent of the AGN optical luminosity over ∼ 25 years. The emission by hot dust warmed directly by the optical/UV AGN output has increased gradually by ∼ 4%/year, indicating a possibly growing torus. A third dust component at ∼ 700 K does not seem to participate directly in the IR reverberation behavior and its emission may originate deep in the circumnuclear torus. We find a reverberation signal at ∼ 10 µm with an inferred radius for the warm dust of ∼2.6 pc. The lack of variability at 20-40 µm indicates the far-IR emission comes from even more extended regions. The torus properties revealed by dust reverberation analysis are inconsistent with predictions from pure clumpy torus models. Instead, the NGC 4151 torus appears to be flared, allowing direct dust heating by the nucleus over radial distances of ∼0.03 to 3 pc. We integrate our results with previous work for a complete picture of the AGN dusty environment.

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