ANALYSIS OF THE IONIZED-HYDROGEN MOTIONS IN THE DIRECTION OF THE CYG OB1 AND CYG OB3 ASSOCIATIONS

Interferometric H-alpha observations of the system of shells in the re gion of the Cyg OB1 and Cyg OB3 associations are presented. The ionize d-hydrogen radial-velocity field is studied in the region I similar to 725 degrees-79 degrees, b similar to 1 degrees-4 degrees. The main co mponent in the line profile is observed in the radial-velocity interva l Delta V-LSR = 2-20 km/s. A decrease in the radial velocity of the ma in component with longitude is noted, due to the differential rotation of the Galaxy. A comparison of the observed run of mean velocity with that expected for various distances suggests that most of the radiati ng ionized gas in the direction of Cyg OB1 is at a distance of 1.5-2 k pc. This is consistent with the mean photometric distance to stars in this association. In some regions, a secondary line maximum is observe d at high positive or negative velocities, at a level no less than 30- 35% of the maximum intensity of the main component. High-velocity moti ons at negative velocities up to V-LSR = -85 km/s have been observed o n multiple occasions, including in interstellar absorption lines in th e spectra of the stars of Cyg OB1 and Cyg OB3. The widespread presence of regions with high positive velocities V-LSR = 30-55 km/s is report ed here for the first time. The relation between the spatial distribut ions of the molecular and ionized components of the shell complex is d iscussed. It is concluded that the multiple-shell system formed as the result of an interaction between the stars of the Cyg OB1 association and a dense molecular complex. At the western edge of the multiple-sh ell system, there is some contribution from the stars of the Cyg OB3 a ssociation, and, at the eastern edge, there is a significant contribut ion from the stars of Cyg OB9 and from two WR stars at a distance of a bout 900 pc.