Extensive X-ray monitoring of the broad-line radio galaxy 3C 382.

Abstract

The results of an intensive monitoring campaign of the X-ray light curve of the broad- line radio galaxy 3C 382, performed using the EXOSAT observatory over a five-month period in summer 1985, are presented. Significant variations on a time-scale of several days are found in both the hard and soft X-ray bands, probably superimposed on a systematic long-term (months) trend. However, no evidence was found for such variability on shorter ( <6 hr) time-scales. A variable soft excess is seen with the Low Energy telescope. The soft excess seems coupled to the hard X-ray continuum on long time-scales (months) but not on short time- scales (weeks or less). We suggest that long-term variations could be associated with a common power source for both soft and hard X-ray emission, perhaps associated with details of the accretion process, while rapid variability may indicate different emission mechanisms in the two energy bands.