Two- and Three-Dimensional Hydrodynamical Simulations of Mass Transfer in Semidetached Binaries with Explicit Radiative Cooling and Self-Absorption in Their Gaseous Envelopes

Abstract

We have modeled the mass transfer in three Algol-type binaries using two-and three-dimensional numerical hydrodynamical techniques. Radiative cooling and absorption in the envelopes surrounding the components of the close binaries are explicitly taken into account. The resulting envelope temperatures are consistent with those observed. We derived these temperatures by considering the energy balance in the moving gas, including heating due to the numerical viscosity that is inherent to the simulations and radiative cooling. The radiative cooling was calculated assuming an optically thin plasma in a state of ionization balance. Taking into account both of these processes yielded temperatures of 4000–30 000 K in the disk around the accreting primary and in the common envelope surrounding the close binary. Our computations also indicate that the envelope morphology is not sensitive to the radiative-cooling model used.