Related papers: A novel method to bracket the corotation radius in…
We use the largest open clusters catalogue in the post-Gaia era to provide the observational view of the Galactic disk. By compiling the physical parameters like age, distance, and kinematic information, we investigate the spatial…
A photometric method for quantifying deviations from axisymmetry in optical images of disk galaxies is applied to a sample of 32 face-on and nearly face-on spirals. The method involves comparing the relative fluxes contained within…
The spiral structure of a spiral galaxy can be seen through different observational tracers such as the dust in the interstellar medium, the free electrons in ionized regions, the molecular gas, or the atomic hydrogen in H{\alpha} regions.…
We try to determine the Galactic structure by comparing the observed and modeled velocities of OB-associations in the 3 kpc solar neighborhood. We made N-body simulations with a rotating stellar bar. The galactic disk in our model includes…
A new method of evaluating relative (arm with respect to the interarm disk) star formation rates and relative star formation efficiencies, together with spiral arm-amplitudes, as a function of the galactocentric radius, using broad-band…
The Milky Way spiral arms are well established from star counts as well as from the locus of molecular clouds and other young objects, however, they have only recently started to be observed from a kinematics point of view. Using the…
In this work we revisit the issue of the rotation speed of the spiral arms and the location of the corotation radius of our Galaxy. This research was performed using homogeneous data set of young open clusters (age < 50 Myr) determined from…
Within Rotation Curves (RC) is encoded the kinematical state of the stellar disc as well as information about the dynamical mechanisms driving the secular evolution of galaxies. To explain the characteristic features of RCs that arise by…
An N-body hybrid simulation, integrating both massive and tracer particles, of a Galactic disk is used to study the stellar phase space distribution or velocity distributions in different local neighborhoods. Pattern speeds identified in…
We analyse the secular effects of a long-lived Galactic spiral structure on the stellar orbits with mean radii close to the corotation resonance. By test-particle simulations and different spiral potential models with parameters constrained…
The Galactic disk exhibits complex chemical and dynamical substructure thought to be induced by the bar, spiral arms, and satellites. Here, we explore the chemical signatures of bar resonances in action and velocity space and characterize…
We investigate the correlations in galaxy shapes between optical and radio wavelengths using archival observations of the COSMOS field. Cross-correlation studies between different wavebands will become increasingly important for precision…
Spiral galaxies are observed to exhibit a range of morphologies, in particular in the shape of spiral arms. A key diagnostic parameter is the pitch angle, which describes how tightly wound the spiral arms are. Observationally and…
We examine the distribution of young stars associated with the spiral arms of a simulated L* cosmological disk galaxy. We find age patterns orthogonal to the arms which are not inconsistent with the predictions of classical density wave…
One of the striking discoveries of protoplanetary disc research in recent years are the spiral arms seen in several transitional discs in polarised scattered light. An interesting interpretation of the observed spiral features is that they…
We have determined 194 Faraday rotation measures (RMs) of polarized extragalactic radio sources using new, multi-channel polarization observations at frequencies around 1.4 GHz from the Very Large Array (VLA) in the Galactic plane at…
We have observed a snapshot of our N-body/Smoothed Particle Hydrodynamics simulation of a Milky Way-sized barred spiral galaxy in a similar way to how we can observe the Milky Way. The simulated galaxy shows a co-rotating spiral arm, i.e.…
Our Galaxy is a barred spiral. Recent work based on the COBE NIR data implies a small bulge-bar and a disk with a short scale-length. The corotation radius of the bar is in the range 3-4.5 kpc. The stellar density distribution beyond the…
We have developed a method for finding dynamical resonances in disk galaxies using the change in sense of the radial component of the in-plane velocity at a resonance radius. Using simulations we show that we would expect to find these…
Bars may induce morphological features, such as rings, through their resonances. Previous studies suggested that the presence of 'dark-gaps', or regions of a galaxy where the difference between the surface brightness along the bar major…