Conditions and nature of gas flow in spiral-elliptical binary galactic systems

Abstract

The process of gas flow from a spiral to an elliptical galaxy has been modeled numerically in the framework of the circular restricted three-body problem. It has been found that the possibility of gas loss by the spiral galaxy depends strongly on the relationship between the direction of its axial rotation and the orbital motion of the galaxies of the binary system. When these motions are in opposite directions, gas crossflow does not occur. In addition, an important parameter of the problem is the size of the disk of the spiral galaxy. According to the calculations, the rate at which gas can pass to the elliptical galaxy for a statistically average S-E pair with signs of interaction in the catalog of I.D. Karachentsev is /approx/0.2M/circled dot/ per year. This value is quite sufficient to explain the enhanced abundance of neutral hydrogen (/approx/10/sup 8/ M/circled dot/) in a number of galaxies of early types. The calculations have also shown that during the time of one or two revolutions of the disk of the spiral galaxy there is a strong distortion of its shape by the tidal interaction. This fact must be taken into account when the individual masses of spiral galaxiesmore » belonging to binary systems are determined from the rotation curves.« less