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As part of a long-term project to revisit the kinematics and dynamics of the large disc galaxies of the Local Group, we present the first deep, wide-field (42 x 56) 3D-spectroscopic survey of the ionized gas disc of Messier 33. Fabry-Perot interferometry has been used to map its Ha distribution and kinematics at unprecedented angular resolution (<3) and resolving power (12600), with the 1.6m telescope at the Observatoire du Mont Megantic. The ionized gas distribution follows a complex, large-scale spiral structure, unsurprisingly coincident with the already-known spiral structures of the neutral and molecular gas discs. The kinematical analysis of the velocity field shows that the rotation center of the Ha disc is distant from the photometric center by 170 pc (sky projected distance) and that the kinematical major-axis position angle and disc inclination are in excellent agreement with photometric values. The Ha rotation curve agrees very well with the HI rotation curves for 0 < R < 6.5 kpc, but the Ha velocities are 10-20 km/s higher for R > 6.5 kpc. The reason for this discrepancy is not well understood. The velocity dispersion profile is relatively flat around 16 km/s, which is at the low end of velocity dispersions of nearby star-forming galactic discs. A strong relation is also found between the Ha velocity dispersion and the Ha intensity. Mass models were obtained using the Ha rotation curve but, as expected, the dark matter halos parameters are not very well constrained since the optical rotation curve only extends out to 8 kpc.
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 signifi
(Abridged) We study the properties of anisotropic and axisymmetric velocity ellipsoids from maps of the gas velocity dispersion in nearby galaxies. This data allow us to measure the azimuthal-to-radial axis ratio of gas velocity ellipsoids, which is
For the Local Group Scd galaxy M 33 this paper presents a multi-scale study of the relationship between the monochromatic star formation rate (SFR) estimator based on 12 $mu$m emission and the total SFR estimator based on a combination of far-ultravi
[Abridged] 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 dy
We present new abundance measurements for eleven GCs in the Local Group galaxies NGC 147, NGC 6822, and Messier 33. These are combined with previously published observations of four GCs in the Fornax and WLM galaxies. The abundances were determined f