ar X iv : a st ro - p h / 96 01 04 5 v 1 1 0 Ja n 19 96 The nature of the X - ray source in NGC 4151
نویسندگان
چکیده
Analysis of broad-band X/γ-ray spectra of NGC 4151 shows that the data are well modelled with an intrinsic spectrum due to thermal Comptonization with temperature ∼ 50 keV and X-ray spectral index α ∼ 0.4– 0.7. The variable X-ray spectrum pivots at ∼ 100 keV, which is consistent with the observed approximatly constant γ-ray spectrum. The observed UV/X-ray correlation can be explained by two specific models with reprocessing of X-rays by cold matter. The first one is based on ree-mission of the X-ray flux absorbed by clouds in the line of sight. The second assumes reprocessing of X-rays and γ-rays by a cold accretion disk with a dissipative patchy corona.
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