NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-08-22 T19:56:46 PDT
Help | Comment | NED Home

For refcode 1990A&A...233...53W:
Retrieve 1 NED object in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by European Southern Observatory (ESO). Reproduced by permission
1990A&A...233...53W The variable ultraviolet absorption lines in the Seyfert 1 galaxy NGC 3516 R. Walter, M. -H. Ulrich, T. J. -L. Courvoisier, and L. M. Buson, Geneva Observatory, Chemin des Maillettes 51, CH-1290 Sauverny, Switzerland European Southern Observatory Karl-Schwarzschild-SNR. 2, D-8046 Garching, Federal Republic of Germany Osservatorio Astronomico, Vicolo Osservatorio 5, 1-35122 Padova, Italy Received August 8, 1989; accepted February 23, 1990 Abstract. The ultraviolet spectrum of the Seyfert 1 galaxy NGC 3516 shows several intrinsic variable absorption lines. We analyze the properties of the CIV absorption profile, using IUE observations performed between 1978 and 1989. With certain assumptions which are supported by the observations and spelled out in the text, we are able to successfully model the absorption line with a narrow component (FWHM <~ 500 km s^-1^) and a broader component variable in width and depth. For all epochs the correlation between the column density (N_CIV_) of the broad component and the continuum flux at 1550 A is only fair, but this correlation is very good and linear during two periods of 1.5 years and 2.3 years. From this we deduce that the absorbing material is at a typical distance of 10^18^ cm from the ionizing source, and that it is in clouds of typical geometrical thickness of 10^15^ cm. A cloud stays on the line of sight for a period of 1 to 2 years. Key words: Galaxies: NGC 3516 - Galaxies: Seyfert
Retrieve 1 NED object in this reference.
Please click here for ADS abstract

Back to NED Home