The Canadian Galactic Plane Survey

Abstract

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.

3D hydrodynamic simulations of the Galactic supernova remnant CTB 109

“…However, no radio emission has been detected from the AXP. The analysis of CO observations (Tatematsu et al 1987;Kothes et al 2002;Taylor et al 2003) has revealed that the western part of the SNR has encountered a giant molecular cloud (GMC) complex, resulting in a semicircular shape of the remnant. Moreover, in radio a double-shell structure can be seen (see Fig.…”

“…Recent measurements show that the distance to CTB 109 lies between 3 and 4 kpc (Kothes et al 2002;Tian et al 2010); the latest value is 3.2 ± 0.2 kpc (Kothes & Foster 2012). It is even more difficult to determine the proper motion of A&A 582, A47 (2015) (Kothes et al 2002) from the Canadian Galactic Plane Survey (CGPS, Taylor et al 2003). Right: intensity map (0.3−4.0 keV) of CTB 109 in false colour from the XMM-Newton EPIC data (Sasaki et al 2004).…”

Dark Hydrogen in the Galactic Plane

“…21cm line data from the Canadian [12], Southern [8], and VLA [13] Galactic Plane Survey components of the IGPS reveal a rich and subtle population of HISA features, many of which are invisible at lower resolutions. Analyses of several CGPS and SGPS features [4,6,7] find temperatures of a few tens of Kelvins and densities of order ¡ cm5 7 6 .…”

The infrared and molecular environment surrounding the Wolf-Rayet star WR 130

“…In this paper, we use the 1420 MHz radio continuum image of the WR 130 area from the Canadian Galactic Plane Survey (CGPS - Taylor et al 2003). Because this image is the result of a mosaic containing more than one pointing field, it has a slightly better signal-to-noise ratio and dynamic range.…”