Broad emission line variability in the Seyfert 1 galaxies NGC 5548 and NGC 3783

• High quality spectra are presented for the Seyfert 1 galaxies NGC 5548 and NGC 3783. Halpha and Hbeta were observed at different epochs, with time intervals between 4 and 13 months. The spectra have been scaled to each other by normalizing the flux of the narrow lines. The difference spectra show that the broad emission lines have varied not only in flux, but also in shape. The authors compare their data with those published by Peterson (1987) and Peterson et al. (1987) and conclude that the supermassive binary scenario proposed by the latter is not unique. The observed variations can be interpreted in an accretion disk scenario. The whole data-set also provides evidence against models based on outflowing motion. The He II lambda4686 line discussed together with N III lambda4640 Bowen emission. A limit to the results is given by the long time intervals separating the observations, which do not allow the authors to set as strong constraints on the BLR as high quality, frequent monitoring of Seyfert 1 spectra would

Ämnesord

NATURVETENSKAP  -- Fysik -- Astronomi, astrofysik och kosmologi (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Astronomy, Astrophysics and Cosmology (hsv//eng)

Nyckelord

Experimental/ astronomical spectra

Seyfert galaxies

visible astronomical observations/ AD 1985 to 1986

visible

Seyfert 1 galaxies

NGC 5548

NGC 3783

spectra

Halpha

Hbeta

broad emission lines

flux

shape

supermassive binary scenario

accretion disk scenario

outflowing motion

He II

N III

Bowen emission

468.6 nm

464 nm

N

He

H/ A9580J Photographic region astronomical observations A9850E Galactic structure

content and morphology A9850R Active and peculiar galaxies/ wavelength 4.686E-07 m

wavelength 4.64E-07 m/ N/el

He/el

H/el

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)