作者
BM Peterson, TJ Balonek, ES Barker, J Bechtold, R Bertram, NG Bochkarev, MJ Bolte, D Bond, TA Boroson, MT Carini, TE Carone, JA Christensen, SD Clements, AL Cochran, RD Cohen, D Crampton, M Dietrich, Martin S Elvis, A Ferguson, AV Filippenko, KJ Fricke, CM Gaskell, JP Halpern, J Huchra, JB Hutchings, W Kollatschny, AP Koratkar, KT Korista, JH Krolik, NJ Lame, A Laor, RJ Leacock, GM MacAlpine, MA Malkan, D Maoz, HR Miller, SL Morris, H Netzer, CLM Oliveira, J Penfold, MV Penston, E Perez, RW Pogge, MW Richmond, W Romanishin, EI Rosenblatt, L Saddlemyer, A Sadun, SR Sawyer, JC Shields, AI Shapovalova, AG Smith, HA Smith, PS Smith, W-H Sun, U Thiele, TJ Turner, S Veilleux, RM Wagner, RJ Weymann, Belinda Jane Wilkes, BJ Wills, D Wills, PF Younger
发表日期
1991
期刊
The Astrophysical Journal
出版商
IOP Publishing
简介
A large, international program of ground-based optical spectroscopy and photometry of the variable Seyfert 1 galaxy NGC 5548 undertaken in support of an IUE monitoring campaign is described. This contribution presents the data base and describes the methods used to correct for systematic differences between spectra from different sources. Optical continuum and H-beta emission-line light curves are derived from the spectra. The behavior of the optical continuum is qualitatively the same as the behavior of the ultraviolet continuum. Cross-correlation of the ultraviolet and optical continuum measurements does not reveal any significant lag between them. The h-beta emission-line variations show the same basic pattern as seen in the continuum and ultraviolet emission lines, with H-beta lagging behind the continuum by about 20 days. This is significantly larger than the about 10 day lag deduced for Ly-alpha.
引用总数
学术搜索中的文章
BM Peterson, TJ Balonek, ES Barker, J Bechtold… - The Astrophysical Journal, 1991