The Canadian Galactic Plane Survey (CGPS) is a project to combine radio, millimetre and infrared surveys of the Galactic Plane to provide arc-minute scale images of all major components of the interstellar medium over a large portion of the Galactic disk. We describe in detail the observations for the low-frequency component of the CGPS, the radio surveys carried out at the Dominion Radio Astrophysical Observatory (DRAO), and summarize the properties of the merged database of surveys that comprises the CGPS.The DRAO Synthesis Telescope surveys have imaged a 73 • section of the Galactic Plane, using ∼85% of the telescope time between April 1995 and June 2000. The observations provide simultaneous radio continuum images at two frequencies, 408 MHz and 1420 MHz, and spectralline images of the λ21-cm transition of neutral atomic hydrogen. In the radio continuum at 1420 MHz dual-polarization receivers provide images in all four Stokes parameters. The surveys cover the region 74.2 • < < 147.3 • , with latitude extent of −3.6 • < b < +5.6 • at 1420 MHz and −6.7 • < b < +8.7 • at 408 MHz. By integration of data from single-antenna observations, the survey images provide complete information on all scales of emission structures down to the resolution limit, which is just below 1 × 1 cosec(δ) at 1420 MHz, and 3.4 × 3.4 cosec(δ) at 408 MHz. The continuum images have dynamic range of several thousand, yielding essentially noise-limited images with rms of ∼0.3 mJy/beam at 1420 MHz and ∼3 mJy/beam at 408 MHz. The spectral-line data are noise limited with rms brightness temperature ∆T B ∼ 3 K in a 0.82 km s −1 channel.The complete CGPS data set, including the DRAO surveys and data at similar resolution in 12 CO (1-0) and in infrared emission from dust, all imaged to an identical Galactic co-ordinate grid and map projection, are being made publicly available through the Canadian Astronomy Data Centre.

We present a new catalogue containing all known Galactic supernova remnants observed in phase I and II of the Canadian Galactic Plane Survey (65. Stokes I images at 1420 MHz of 34 SNRs and at 408 MHz of 36 SNRs are displayed. From these 1 and 3 -resolution data (respectively) we determine accurate centre positions and angular dimensions. The flux densities at 1420 and 408 MHz are integrated and combined with values from the literature to define more accurate radio spectra. The CGPS polarization data at 1420 MHz were examined and significant linear polarization from 18 SNRs is found, with a modest signal from 6 others.

Abstract. The Orion local spiral arm is seen tangential towards the Cygnus region. Intense radio emission with quite a complex morphology is observed, which appears to be surrounded by strong soft X-ray emission. This remarkable X-ray structure is known as the Cygnus superbubble. We compare a recent 1.4 GHz radio continuum and polarization map from the Effelsberg 100-m telescope with X-ray data from the ROSAT all-sky survey of this area. Including available survey data of the infrared, H i and CO emission, we investigate a number of high latitude features, which are physically related to one of the Cygnus OB associations. These OB associations, however, are located along the local arm at different distances. Our results support the view that the Cygnus superbubble is not a physical unity, but results from a projection of unrelated X-ray emitting features at different distances blown out from the local arm seen along the line of sight.