Abstract We present the preliminary results of a study of the soft X-ray properties of a sample of 34 BL Lacertae objects observed with the the EXOSAT Observatory. Strong correlations between the X-ray, optical and radio fluxes have been found in the subsample of X-ray selected objects. X-ray variability is common and has been significantly detected in 14 (8 × ray-selected and 6 radio-selected) out of the 25 objects observed more than once. Flux variations by up to a factor 5 have been found. The commonest form of variability encountered consists of small amplitude variations about a quiescent flux level whose mean value remains roughly constant over time scales of years.


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    Title :

    X-ray time variability and luminosity correlations in BL lacertae objects


    Contributors:
    Giommi, P. (author) / Barr, P. (author) / Garilli, B. (author) / Maccagni, D. (author) / Pollock, A. (author)

    Published in:

    Publication date :

    1988-01-01


    Size :

    5 pages




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English



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