Astronomy and Astrophysics – Astrophysics
Scientific paper
Oct 1991
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1991a%26a...250..312w&link_type=abstract
Astronomy and Astrophysics (ISSN 0004-6361), vol. 250, no. 2, Oct. 1991, p. 312-315. Research supported by SNSF.
Astronomy and Astrophysics
Astrophysics
10
Active Galactic Nuclei, Iue, Seyfert Galaxies, Ultraviolet Spectra, Variability, X Ray Sources
Scientific paper
Large observation campaigns of Seyfert galaxies give the opportunity to check the linearity of IUE short wavelength camera at low flux number and moderate background. In particular, many pairs of quasi-simultaneous observations of NGC 5548 have been obtained with IUE. Pairs of spectra which include one well exposed and one poorly exposed spectrum were selected. The ratio of the two broad band continuum fluxes measured in these paired spectra is variable and well correlated to the integrated flux of the underexposed observation indicating that this apparent variability is due to instrumental effects rather than source variability. The response of the SWP system (camera + processing) decreases by up to 25 percent at low flux numbers. Taking these nonlinearities into account, NGC 5548 did not show variability in the UV on time scale of a few hours as in the soft X-ray.
Courvoisier Thierry J. -L.
Walter Robert
No associations
LandOfFree
Search for fast ultraviolet variability in NGC 5548 and non-linearities in IUE's SWP camera 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 Search for fast ultraviolet variability in NGC 5548 and non-linearities in IUE's SWP camera, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Search for fast ultraviolet variability in NGC 5548 and non-linearities in IUE's SWP camera will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1874573