Related papers: Re-determining the Galactic spiral density wave pa…
We perform numerical simulations of a stellar galactic disk with initial conditions chosen to represent an unrelaxed population which might have been left following a merger. Stars are unevenly distributed in radial action angle, though the…
We present radio intensity and polarisation profiles of 28 $\gamma$-ray-detected pulsars with the aim of putting constraints on their viewing geometries using data from the Parkes telescope. Constraints are formed both from the…
The large-scale magnetic field of our Galaxy can be probed in three dimensions using Faraday rotation of pulsar signals. We report on the determination of 223 rotation measures from polarization observations of relatively distant southern…
We report a trigonometric parallax of 12 GHz methanol masers associated with the massive star forming region G9.62+0.20, corresponding to a distance of 5.2+-0.6 kpc. With a local standard of rest velocity of about 2 km/s, the region's…
We present the results of PSR$\pi$, a large astrometric project targeting radio pulsars using the Very Long Baseline Array (VLBA). From our astrometric database of 60 pulsars, we have obtained parallax-based distance measurements for all…
The peculiar velocity of a mass tracer is on average aligned with the dipole modulation of the surrounding mass density field. We present a first measurement of the correlation between radial peculiar velocities of objects in the…
We have measured gas and stellar velocity dispersions in 5 circumnuclear starforming regions (CNSFRs) and the nucleus of the barred spiral galaxy NGC 3351. The stellar dispersions have been obtained from high resolution spectra of the CaT…
Radio-wave scattering is enhanced dramatically for Galactic center sources in a region with radius >~ 15 arc min. Using scattering from Sgr A* and other sources, we show that pulse broadening for pulsars in the Galactic center is {\em at…
Extended halo tidal streams from disrupting Milky Way satellites offer new opportunities for gauging fundamental Galactic parameters without challenging observations of the Galactic center. In the roughly spherical Galactic potential tidal…
To estimate the peculiar velocity of the Sun with respect to the Local Standard of Rest (LSR), we used young objects in the Solar neighborhood with distance measurement errors within 10%-15%. These objects were the nearest Hipparcos stars…
Some galactic theories of spiral arms predict an offset between different tracers of star formation. Our goal here is to find such an offset between the observed location of radio masers and the location of the arms, using a recent 4-arm…
We determine the total dynamical density in the solar neighbourhood using the Tycho-Gaia Astrometric Solution (TGAS) catalogue. Astrometric measurements of proper motion and parallax of stars inform us of both the stellar number density…
Density waves in galaxy disks have been proposed over the years, in a variety of specific models, to explain spiral arm structure and its relation to the mass distribution, notably in barred galaxies. An important parameter in dynamical…
We explore the longitude-velocity distribution of 6.7-GHz methanol masers in the context of the inner structure of our Galaxy. We analyse the correlation in velocities within this distribution and identify density enhancements indicating…
Aside from the grand-design stellar spirals appearing in the disk of M81, a pair of stellar spiral arms situated well inside the bright bulge of M81 has been recently discovered by Kendall et al. (2008). The seemingly unrelated pairs of…
We estimated the Galactic model parameters for a set of 36 high-latitude fields included in the currently available Data Release 5 (DR 5) of the Sloan Digital Sky Survey ({\em SDSS}), to explore their possible variation with the Galactic…
A new approach to determining the solar galactocentric distance, $R_0$, from the geometry of spiral-arm segments is proposed. Geometric aspects of the problem are analyzed and a simplified three-point method for estimating $R_0$ from…
We study the vertical perturbations in the galactic disc of the Milky Way-size high-resolution hydrodynamical cosmological simulation named GARROTXA. We detect phase spirals in the vertical projection $Z- V_{Z}$ of disc's stellar particles…
We estimated the Galactic model parameters by means of a new approach based on the comparison of the observed space density functions per absolute magnitude interval with a unique density law for each population individually, and via the…
The spiral arms spanning disk galaxies are believed to be created by density waves that propagate through galactic disks. We present a novel method of finding the co-rotation radius where the spiral arm pattern speed matches the velocities…