Hydrodynamic Processes in Young Binary Systems as a Source of Cyclic Variations of Circumstellar Extinction - AstrophysicsReport as inadecuate




Hydrodynamic Processes in Young Binary Systems as a Source of Cyclic Variations of Circumstellar Extinction - Astrophysics - Download this document for free, or read online. Document in PDF available to download.

Abstract: Hydrodynamic models of a young binary system accreting matter from theremnants of a protostellar cloud have been calculated by the SPH method. It isshown that periodic variations in column density in projection onto the primarycomponent take place at low inclinations of the binary plane to the line ofsight. They can result in periodic extinction variations. Three periodiccomponents can exist in general case. The first component has a period equal tothe orbital one and is attributable to the streams of matter penetrating intothe inner regions of the binary. The second component has a period that is afactor of 5-8 longer than the orbital one and is related to the density wavesgenerated in a circumbinary CB disk. The third, longest period isattributable to the precession of the inner asymmetric region of CB disk. Therelationship between the amplitudes of these cycles depends on the modelparameters as well as on the inclination and orientation of the binary inspace. We show that at a dust-to-gas ratio of 1:100 and and a mass extinctioncoefficient of 250 cm$^2$ g$^{-1}$, the amplitude of the brightness variationsof the primary component in the V-band can reach $1^m$ at a mass accretion rateonto the binary components of $10^{-8} M {\odot}$ yr$^{-1}$ and a $10^{ m o}$inclination of the binary plane to the line of sight. We discuss possibleapplications of the model to pre-main-sequence stars.



Author: N. Ya. Sotnikova, V. P. Grinin

Source: https://arxiv.org/



DOWNLOAD PDF




Related documents