Steps toward Determination of the Size and Structure of the Broad-Line Region in Active Galactic Nuclei. XII. Ground-Based Monitoring of 3C 390.3

Results of a ground-based optical monitoring campaign on 3C 390.3 in 1994-95 are presented. The broad-band fluxes (B, V, R, and I), the spectrophotometric optical continuum flux F(5177) and the integrated emission-line fluxes of Ha, Hb, Hg, HeI, and HeII all show a nearly monotonic increase with episodes of milder short-term variations superposed. The amplitude of the continuum variations increases with decreasing wavelength (4400-9000 A). The optical continuum variations follow the variations in the ultraviolet and X-ray with time delays, measured from the centroids of the cross- correlation functions, typically around 5 days, but with uncertainties also typically around 5 days; zero time delay between the high-energy and low-energy continuum variations cannot be ruled out. The strong optical emission lines Ha, Hb, Hg, and HeI respond to the high-energy continuum variations with time delays typically about 20 days, with uncertainties of about 8 days. There is some evidence that HeII responds somewhat more rapidly, with a time delay of around 10 days, but again, the uncertainties are quite large (~8 days). The mean and rms spectra of the Ha and Hb line profiles provide indications for the existence of at least three distinct components located at +-4000 and 0 km/s relative to the line peak. The emission-line profile variations are largest near line center.Comment: 42 pages (Latex), 13 figures, 14 table

High-Mass Binary Stars

Detailed studies of high-mass binaries in the MWG, LMC and SMC, in which spectral disentangling and cross-correlation methods have been employed, demonstrate good agreement for detached binaries with the new stellar evolution models for single stars with stellar-wind mass loss and stellar rotation, whilst the semi-detached systems are consistent with recent binary-star evolution codes for case A mass exchange. The subject area would benefit from a systematic use of spectral disentangling coupled with more precise determinations of stellar temperatures via model atmosphere fitting to the separated spectra in order to provide more rigorous empirical constraints on the evolution models.</p

An Introductory Review - Modern Methods for Analysing Binary Stars

Observational techniques and data analysis tools have improved markedly in recent years, with the consequence that we can explore the properties of close binary stars at much greater spectral and time resolution and much better signal-to-noise ratios, or to much fainter brightness levels, than hitherto. This introductory review presents some examples to highlight those advances.</p