Modelling the IDV Emissions of the BL Lac Objects with a Langevin Type Stochastic Differential Equation

Journal of Astrophysics and Astronomy (Impact Factor: 0.5). 06/2011; 32(1):189-192. DOI: 10.1007/s12036-011-9026-3
Source: arXiv

ABSTRACT In this paper, we introduce a simplified model for explaining the observations of optical intra-day variability (IDV) of the
BL Lac Objects. We assume that the source of the IDV are the stochastic oscillations of an accretion disk around a supermassive
black hole. The stochastic fluctuations on the vertical direction of the accretion disk are described by using a Langevin
type equation with a damping term and a random, white noise type force. Furthermore, preliminary numerical simulation results
are presented, which are based on the numerical analysis of the Langevin stochastic differential equation.

KeywordsLangevin type stochastic differential equation–BL Lac objects

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Available from: Tiberiu Harko, Feb 25, 2014
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