Calculation of tidal evolution constants for close binary systems

Dryomova, GN, Svechnikov, MA
Kinemat. fiz. nebesnyh tel (Online) 2011, 27(2):8-30
Start Page: Physics of Stars and Interstellar Medium
Language: Russian
Abstract: 

We calculated the tidal torque constants for the components of 112 close eclips ing binaries of the DMS-type (detached components located within the main sequence) from the catalogue developed by Svechnikov and Perevozkina (1999) on the basis of the evolutionary model-tracks proposed by Claret (2004), that in clude for the first time the tidal-evo lution constants to study tidal effects in close binaries. The method of corners ion of the grid of model-tracks into isochrones with an arbitrary small time-step using optimal non-linear interpolation was applied. The small time-step criterion guaranteed the application of the linear interpolation for age estimation of the DMS components and the individual tidal-evolution constant set corresponding to the estimated time for the considered close eclipsing binary. The theoretical values of the apsidal-mo tion period which were calculated from the internal structure constants computed for the components of each close binary agree well with the observational values. This confirms the reliability of evolutionary stellar models developed by Claret and the numerical algorithm proposed here.

Keywords: close binary system, evolutionary stellar model, tidal evolution, tidal torque constants