The Low-Resolution DRAO Survey of H I Emission from the Galactic Plane. II.

In 2000, a survey of H I line emission in the Galactic plane between Galactic longitudes l = 722 and 1490, covering latitudes from b = -54 to 72, made using the 26 m telescope at the Dominion Radio Astrophysical Observatory, was published as part of the Canadian Galactic Plane Survey project. The survey with the 26 m telescope has now been extended to cover longitudes from l = 500 to 1950, between the same latitude limits. In addition, a region at higher Galactic latitudes (b = 74–240) has been surveyed between longitudes l = 964 and 1202. As in the initial survey, spectra were observed at 02 intervals of longitude and latitude (0.33 half-power beamwidths). (In an appendix, it is demonstrated that, when single-antenna data and interferometer data are to be combined, the single-antenna data must be sampled at an interval no greater than 0.5 times the half-power beamwidth of the single antenna. Coarser sampling will result in the introduction of spurious structure into the resulting images.) The spectral resolution is 1.32 km s^-1, and the LSR velocity range is -260–161 km s^-1. The spectra have been corrected for stray radiation and have an estimated T_b scaling accuracy of 1% and an estimated rms noise in one channel (0.8245 km s^-1) of 0.25 K. Regions of suspected strong H I self-absorption have been identified using a statistic characterizing the "complexity" of the observed spectra. Comparison with spectra from the Leiden/Dwingeloo Survey supports the conclusion from our earlier paper that a small percentage (∼1%–2%) of the spectra in the latter survey suffer from calibration errors exceeding 10%. A table of positions of the more discordant spectra is given.