We present a new deep 21-cm survey of the Andromeda galaxy, based on high resolution observations performed with the Synthesis Telescope and the 26-m antenna at DRAO. The Hi distribution and kinematics of the disc are analyzed and basic dynamical properties are given. The rotation curve is measured out to 38 kpc, showing a nuclear peak at 340 km s −1 , a dip at 202 km s −1 around 4 kpc, two distinct flat parts at 264 km s −1 and 230 km s −1 and an increase to 275 km s −1 in the outermost regions. Except for the innermost regions, the axisymmetry of the gas rotation is very good. A very strong warp of the Hi disc is evidenced. The central regions appear less inclined than the average disc inclination of 74 • , while the outer regions appear more inclined. Mass distribution models by ΛCDM Navarro-Frenk-White, Einasto or pseudo-isothermal dark matter halos with baryonic components are presented. They fail to reproduce the exact shape of the rotation curve. No significant differences are measured between the various shapes of halo. The dynamical mass of M31 enclosed within a radius of 38 kpc is (4.7 ± 0.5) × 10 11 M ⊙ . The dark matter component is almost 4 times more massive than the baryonic mass inside this radius. A total mass of 1.0 × 10 12 M ⊙ is derived inside the virial radius. New Hi structures are discovered in the datacube, like the detection of up to five Hi components per spectrum, which is very rarely seen in other galaxies. The most remarkable new Hi structures are thin Hi spurs and an external arm in the disc outskirts. A relationship between these spurs and outer stellar clumps is evidenced. The external arm is 32 kpc long, lies on the far side of the galaxy and has no obvious counterpart on the other side of the galaxy. Its kinematics clearly differs from the outer adjacent disc. Both these Hi perturbations could result from tidal interactions with galaxy companions.

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.

A new deep Hi survey of the galaxy Messier 33 is presented, based on observations obtained at the Dominion Radio Astrophysical Observatory. We observe a perturbed outer gas distribution and kinematics in M33, and confirm the disk warping as a significant kinematical twist of the major axis of the velocity field, though no strong tilt is measured, in agreement with previous work. Evidence for a new low brightness Hi component with anomalous velocity is reported. It harbours a large velocity scatter, as its kinematics both exceeds and lags the rotation of the disk, and leaks in the forbidden velocity zone of apparent counter-rotation. The observations also reveal wide and multiple peak Hi profiles which can be partly explained by crowded orbits in the framework of the warp model. Asymmetric motions are identified in the velocity field, as possible signatures of a lopsided potential and the warp. The mass distribution modeling of the hybrid Hα-Hi rotation curve favours a cuspy dark matter halo with a concentration in disagreement with the ΛCDM dark halo mass-concentration relationship. The total mass enclosed in 23 kpc is 8 10 10 M , of which 11% are stars and gas. At the virial radius of the cuspy halo, the resulting total mass is 5 10 11 M , but with a baryonic mass fraction of 2% only. This strongly suggests a more realistic radius encompassing the total mass of M33 well smaller than the virial radius of the halo, maybe comparable to the size of the Hi disk.

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