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X-ray studies of BL Lac objects with Ginga

  • VI. X-ray Spectra and Variability
  • Conference paper
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BL Lac Objects

Part of the book series: Lecture Notes in Physics ((LNP,volume 334))

Abstract

Recent results on the X-ray measuarements of BL Lac objects with the X-ray astronomy satellite Ginga, which has the best 2 – 35 keV sensitivity so far, are presented. The spectral features and their relation with the intensities have been studied for three sources, PKS2155-304, H0323+022 and Mrk421. None of them have shown a significant hard tail, indicating that the occurrence of the tail must be rare. For PKS2155-304 and Mrk421 the photon index of the spectrum stayed ≈ 2.8 for different intensity levels, but a marked spectral change in correlation with the intensity was observed from H0323+022. The OVV quasar 3C279 was measured in both quiet and flare levels. In the flare, the intensity of 3C279 varied by 20% in 45 min, which corresponds to the largest value of Δ L/ Δ t (7 x 1042 erg s−2) ever observed from quasars.

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Authors and Affiliations

  1. Department of Physics, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, 113, Tokyo, Japan

    Takaya Ohashi

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  1. Takaya Ohashi
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Editor information

L. Maraschi T. Maccacaro M. -H. Ulrich

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© 1989 Springer-Verlag

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Ohashi, T. (1989). X-ray studies of BL Lac objects with Ginga. In: Maraschi, L., Maccacaro, T., Ulrich, M.H. (eds) BL Lac Objects. Lecture Notes in Physics, vol 334. Springer, Berlin, Heidelberg. https://doi.org/10.1007/BFb0031175

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  • DOI: https://doi.org/10.1007/BFb0031175

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  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-51389-6

  • Online ISBN: 978-3-540-46203-3

  • eBook Packages: Springer Book Archive

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