Astronomy and Astrophysics – Astrophysics
Scientific paper
Oct 2005
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005ap%26ss.299..245p&link_type=abstract
Astrophysics and Space Science, Volume 299, Issue 3, pp.245-261
Astronomy and Astrophysics
Astrophysics
2
Galaxies: Active, Galaxies: Individual: Ngc 3227, Galaxies: Nuclei, Galaxies: Seyfert, Galaxies: Emission Lines Variability
Scientific paper
Fifty-three spectrograms in the optical region (3700 7300 Å) with the spectral resolution ˜8 Å have been obtained for the Seyfert nucleus of the galaxy NGC 3227 with the 6-m telescope on January 1977, while the nucleus was in the historically important epoch of its extreme maximum brightness. Width of the slit was 1″, length of the box during the spectra measurements was 1.5″. Data obtained by us and those compiled from literature showed that profiles of the Balmer lines Hα, Hβ and Hγ are different, evidencing that the gas emitting these lines is highly self-absorbed. It was shown that narrow components of the profiles revealed by Rubin and Ford kept their positions (radial velocities) over 25 years. The components showed intensity variations compared to the central one from minimum to maximum of the nucleus brightness. The same variations were observed by us earlier in the emission line profiles of the NGC 7469 nucleus spectrum. Narrow profile components can reflect long-lived flows or jets in the broad line region (BLR). Obtained facts evidenced that long-lived gas streams and flows causing narrow components of broad line profiles presented not only when BLR of accretion disc is strong but when BLR of accretion disc declined. Blue bump at radial velocity of -5000 km/s in Hγ profile was revealed in spectra of high states of the nucleus, which disappeared in low state. One of the interpretations of this event can be in the framework of a model of one-sided or two-sided gas ejection during the high state of the nucleus, positive radial velocities of which being screened out by a circumnuclear disk.
Metik L.
Pronik I. I.
No associations
LandOfFree
Long-Term Variability Of The Optical Emission Lines In The Nuclear Spectrum Of The Seyfert Galaxy Ngc 3227 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Long-Term Variability Of The Optical Emission Lines In The Nuclear Spectrum Of The Seyfert Galaxy Ngc 3227, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Long-Term Variability Of The Optical Emission Lines In The Nuclear Spectrum Of The Seyfert Galaxy Ngc 3227 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1619871