Synthetic Doppler tomograms of gas flows in the binary system IP peg

We have synthesized Doppler tomograms of gas flows in the binary system IP Peg using the results of three-dimensional gas-dynamical computations. Gas- dynamical modeling in combination with Doppler tomography enables identific ation of the key elements of flows in Doppler maps without Solution of an i ll-posed inverse problem. A comparison of the synthetic tomograms with obse rvations shows that, in the quiescent state of the system, the most luminou s components are ( I) the shock wave induced by interaction between the cir cumbinary envelope and the stream from the Lagrange point L-1 (the "hot lin e") and (2) the gas condensation at the apogee of the quasi-elliptical disk . Both the single spiral shock wave arm in the gas-dynamical solution and t he stream from L-1 contribute little to the luminosity. In the active state of the system, when the stream from L-1 does not play an appreciable role and the disk dominates, both areas of enhanced luminosity in the observatio nal tomograms are associated with the two arms of the spiral shock wave in the disk. (C) 2001 MAIK "Nauka/Interperiodica".