Abstract Details
| Name: NAVEEL AHMAD WANI Affiliation: UNIVERSITY OF KASHMIR Conference ID: ASI2015_777 Title : GLOBAL TIME DEPENDENT SOLUTIONS OF STOCHASTICALLY DRIVEN STANDARD ACCRETION DISKS: DEVELOPMENT OF HYDRODYNAMICAL CODE Authors and Co-Authors : NAVEEL A. WANI*, NASEER IQBAL*, RANJEEV MISRA** *Department Of Physics, University Of Kashmir (Srinagar), India. **Inter-University Centre for Astronomy and Astrophysics (IUCAA), Pune, India. Abstract Type : Poster Abstract Category : Extragalactic astronomy Abstract : X-ray binaries are powered by accretion disks around compact objects, where the X-rays are emit- ted from the inner regions while UV emission could arise from the relatively cooler outer parts. There is now increasing evidence that the variability of the X-rays in different timescales is caused by stochastic fluctuations in the accretion disk at different radii. These fluctuations which arise in the outer parts of the disk, propagate inwards to give rise to X-ray variability and hence this model provides a natural connection between the X-ray and UV variability. While there are analytical expressions to qualitatively understand the effect of these stochastic variabilities, quantitative predictions are only possible by a detailed hydrodynamical study of the global time dependent stan- dard accretion solution. For completeness, the study should include the unstable radiation pressure dominated inner disk, the outer regions which may be electron or free-free scattering dominated, the effect of the last stable orbit and the possibility of the dissipated energy being advected to smaller radii. We have started the development of a numerically efficient code to incorporate these effects. The code presently considers gas pressure dominated solutions with the boundary effect of the last stable orbit included. It has been tested for numerical stability. |