KINEMATICS OF THE INTERSTELLAR-MEDIUM IN THE CYG-I REGION

We present H alpha interferometric observations of the northwestern pa rt of the gas and dust complex associated with the Cyg OB1 and OB3 ass ociations. The radial-velocity field of ionized hydrogen in the region l similar to 73.5 degrees-77 degrees and b similar to 1.5 degrees-4 d egrees is studied. Most of the H alpha-line profiles exhibit the main peak and weak features in the blue wings; in individual regions, a sec ondary peak with an intensity that reaches 15-30% of the intensity of the main component is observed. The mean radial velocity of the main c omponent systematically decreases from V-LSR = 18-20 km s(-1) in the s outh of the region to V-LSR = 4-11 km s(-1) in the north. As in our pr evious studies, we associate the motion of ionized hydrogen at a radia l velocity of 4-12 km s(-1), which is determined from the brightest co mponent of the Ha profile, with the differential Galactic rotation. Th e radial velocities of the weak features in the H alpha-line profile a re distributed over the range -100 to -20 km s(-1). In the direction o f the nebulae Simeiz 55, G75.6+3.2, and G74.5+2.2, the distribution of secondary peaks in the line profile makes it possible to reliably ide ntify gas flows at mean velocities V-LSR similar to -55, -35, and -33 km s(-1), respectively. We use our decade-long studies of-the kinemati cs of ionized gas in the multishell complex associated with Cyg OB1 an d OB3 to compile an electronic database of radial velocities in the H alpha line. By now we have obtained more than 1000 interference-filter images and measured the radial velocities at more than 9000 points.