相关论文: Radial migration and vertical action in N-body sim…
The paper claimed that significant radial migration of stars in a stellar disk like that of the Milky Way could not occur. We now think that while the treatment of the effects of molecular clouds was correct, the paper seriously…
Context: According to numerical simulations, stars are not always kept at their birth galactocentric distances but migrate. The importance of this radial migration in shaping galactic light distributions is still unclear. However, if it is…
The colour and metallicity gradients observed in spiral galaxies suggest that the mass-to-light ratio (M*/L) of the stellar disc is a function of radius. This is indeed predicted by chemo-photometric models of galactic discs. We investigate…
Spiral density wave theory attempts to describe the spiral pattern in spiral galaxies in terms of a long-lived wave structure with a constant pattern speed in order to avoid the winding dilemma. The pattern is consequently a rigidly…
We identify migrating stars in an N-body simulation of a Milky-Way-like disk. Outward migration can occur when a star in a low eccentricity orbit lags a short-lived local spiral arm density peak. We interpret short lived local density…
This thesis investigates the dynamical effect of two structural components of disk galaxies, namely, the dark matter halo and the interstellar gas on the origin and persistence issue of spiral structure in disk galaxies through theoretical…
Thanks to the ever increasing computational power and the development of more sophisticated algorithms, numerical N-body simulations are now uncovering several phenomenological relations between the physical properties of dark matter haloes…
Albeit radial migration must be a ubiquitous process in disc galaxies, its significance in the evolution of stellar discs is not always reflected through global trends. However, there are other key observables, such as the metallicity…
We study how migration affects stars of a galaxy with a thin stellar disc and thicker stellar components. The simulated galaxy has a strong bar and lasting spiral arms. We find that the amplitude of the churning (change in angular momentum)…
The conservation of stellar actions is a fundamental assumption in orbit reconstruction studies in the Milky Way. However, the disc is highly dynamic, with time-dependent, non-axisymmetric features like transient spiral arms and giant…
We run N-body smoothed particle hydrodynamics (SPH) simulations of a Milky Way sized galaxy. The code takes into account hydrodynamics, self-gravity, star formation, supernova and stellar wind feedback, radiative cooling and metal…
Astronomers recently discovered a non-trivial radial motion of stars within our galaxy and were able to reproduce the results using n-body numerics. I modeled a protoplanitary-like disk within a newtonian $\infty$-body problem and…
We study the presence and importance of stellar migration in the evolution of 17 Milky-Way like disk galaxies with stellar mass $10 < \textrm{log}(M_{*}/{\rm M}_\odot) < 11$ from the Auriga suite of zoom-in cosmological hydrodynamical…
We investigate the stellar kinematics of the Galactic disc in 7 $<$ $R$ $<$ 13\,kpc using a sample of 118\,945 red giant branch (RGB) stars from LAMOST and Gaia. We characterize the median, dispersion and skewness of the distributions of…
We seek to understand the origin of radial migration in spiral galaxies by analyzing in detail the structure and evolution of an idealized, isolated galactic disk. To understand the redistribution of stars, we characterize the…
In order to understand the physical mechanisms underlying non-steady stellar spiral arms in disk galaxies, we analyzed the growing and damping phases of their spiral arms using three-dimensional $N$-body simulations. We confirmed that the…
Recent N-body simulations indicate that a thick disc of dark matter, co-rotating with the stellar disc, forms in a galactic halo after a merger at a redshift $z<2$. The existence of such a dark disc component in the Milky Way could affect…
We explore the dependence of the radial alignment of subhalos on the mass of the host halo they orbit in. As the effect is seen on a broad range of scales including massive clusters as well as galactic systems it only appears natural to…
The evolution and distribution of the angular momentum of dark matter (DM) halos have been discussed in several studies over the past decades. In particular, the idea arose that angular momentum conservation should allow to infer the total…
Disc non-axisymmetrc components, such as spirals and central bars, are nowadays known to play an important role in shaping galactic discs. Here we use Tree-SPH N-body simulations to examine the effect of these perturbers on two aspects: the…