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Thermal Comptonization and Disk Thermal Reprocessing in NGC 3516

James Chiang·Omer Blaes
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Abstract

We present an application of the thermal Comptonization/disk reprocessing model recently proposed by Zdziarski, Lubiński, & Smith. We show that the absence of strong optical variations in the presence of strong concurrent X-ray variations, similar to those found by HST/RXTE monitoring observations of NGC 3516, can be explained by changing the geometry of the Comptonizing plasma rather than the accretion disk itself. The total X-ray luminosity of the Comptonizing plasma must decrease as its spatial extent increases. In contrast, the disk inner radius must be roughly fixed in order not to produce optical/ultraviolet color variations stronger than observed. By including emission due to internal viscous dissipation in the disk, we can roughly match the optical and X-ray flux levels and variability amplitudes seen from NGC 3516 during the HST/RXTE campaign.

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James Chiang, Omer Blaes. 2001-07-03. Thermal Comptonization and Disk Thermal Reprocessing in NGC 3516. https://doi.org/10.1086/323077

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