The Bell Laboratories H I survey

Results of observations of the sky north of delta = -40 deg in the 21-cm line of atomic hydrogen are reported. The survey covers a velocity range of 654 km/s centered on the Galactic standard of rest, with 5.3-km/s wide filters. Calibration and reduction of the observations are described. The survey is presented as a series of images of the sky, each covering a 10-km/s wide velocity range. This survey is distinguished by its sensitivity to low surface brightness features (TA is approximately equal to 50 mK) and relative freedom from sidelobe contamination. High-velocity clouds are extracted and cataloged automatically. At the resolution of the survey, the lowest H I column density in the sky is 5.7 x 10 exp 19/cm.