The Cygnus X region. XVII. H 110 alpha and H2 CO line surveys with the 100 m-RT.

A survey of the brightest features in the Cyg X region in H 110-alpha emission and the H2CO absorption line near 6 cm with the Effelsberg 100-m radio telescope is presented. The resolution is 2.6 arcmin. S/N of greater than 5 was achieved for the recombination line, and an apparent optical depth of greater than 0.05 in the H2CO could be detected for a continuum brightness temperature of 2 K. The H 110-alpha lines can be interpreted using the LTE approach, and unusually broad lines are ascribed to blending. The radial-velocity distribution of both does not show any support for the superbubble picture of the area advanced a few years ago (Bocharev and Sitnik, 1985). Two H II regions with large negative velocities are located in the Pers spiral arm. Many details of individual sources are discussed, especially DR7 and DR 21.