Abstract
Two homogeneous models for the steep X-ray spectrum of BL Lacs are discussed, assuming that the X-ray emission is not beamed. If X-rays are synchrotron emission, then they must be produced by a steep power law electron distribution, which is necessarily much flatter at low energies, and corresponds to continuous injection of particles above some minimum relativistic energy. Alternatively, the observed X-rays can be produced by thermal Comptonization of synchrotron photons by relatively cool particles. Pair production in synchrotron self Compton models can yield pairs of sufficient optical depths and temperatures to produce a steep Comptonized spectrum in the soft X-ray band.
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© 1989 Springer-Verlag
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Ghisellini, G. (1989). On the steep X-ray spectrumof BL Lac objects. 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/BFb0031181
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DOI: https://doi.org/10.1007/BFb0031181
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