Astronomy and Astrophysics – Astrophysics
Scientific paper
Sep 1986
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1986esasp.263..621u&link_type=abstract
In ESA Proceedings of an International Symposium on New Insights in Astrophysics. Eight Years of UV Astronomy with IUE p 621-62
Astronomy and Astrophysics
Astrophysics
8
Bl Lacertae Objects, Galactic Nuclei, Galactic Radiation, Ultraviolet Spectra, Variability, Galaxies, Iue, Statistical Analysis
Scientific paper
Over 50 IUE spectra of the brightest known BL Lac object at ultraviolet wavelengths, PKS 2155-304, were reanalyzed using Gaussian extraction techniques that maximize the signal-to-noise. The ultraviolet continuum of PKS 2155-304 is well fitted by a power law model Fv varies as V-alpha, with an average spectral index for the combined SWP-LWR-P fits of less than alpha greater than 0.89 + or - 0.11 (standard deviation). While the ultraviolet intensity of PKS 2155-304 varies by a factor of 2, the spectral index changes very little and is uncorrelated with intensity. Timescales for ultraviolet variability are as short as 10 days. In one case, a well-matched pair of IUE images was obtained nearly simultaneously with a very soft X-ray measurement; the combined spectra clearly show a steepening between the ultraviolet and soft X-ray bands. The relevance of these findings to jet models and accretion models is discussed.
No associations
LandOfFree
Seven years of IUE observations of the BL Lacertae object PKS 2155-304 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 Seven years of IUE observations of the BL Lacertae object PKS 2155-304, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Seven years of IUE observations of the BL Lacertae object PKS 2155-304 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1295108