Abstract
X-ray spectra of the BL Lac type object Mkn 421 and several Seyfert type 1 galaxies; IIIZw2, MCG8-11-11 and NGC 4151, have been obtained using the Leicester University instrument on board the Ariel-6 satellite. The Mkn 421 spectrum is best represented by two powerlaw components, the soft component having α ∼ 3.4 whilst the hard flux has α ∼ 1.0. In MCG8-11-11 there is clear evidence for spectral variability between our observation in late 1979 and that of HEAO-1/A2 in 1977. The Ariel-6 spectrum of MCG8-11-11 can be fitted by a powerlaw of index α ∼ 2.1 together with an iron line at ∼ 6.2 keV with an equivalent width of ∼ 1.6 keV. The first X-ray spectrum of IIIZw2 is also presented, fitting with a powerlaw we find an index of α ∼ 1.7. With the exception of NGC 4151 there is no evidence for a significant column of cool material along the line of sight.
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Hall, R., Ricketts, M.J., Page, C.G. et al. Ariel-6 medium energy spectral observations of active galaxies. Space Sci Rev 30, 47–54 (1981). https://doi.org/10.1007/BF01245998
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DOI: https://doi.org/10.1007/BF01245998