Related papers: Orbit decay in encounters between anisotropic sphe…
Following earlier authors, we re-examine constraints on the radial velocity anisotropy of generic stellar systems using arguments for phase space density positivity, stability, and separability. It is known that although the majority of…
When galaxies collide, dynamical friction drives their central supermassive black holes close enought to each other such that gravitational radiation becomes the leading dissipative effect. Gravitational radiation takes away energy,…
We study resolution effects in numerical simulations of gas-rich and gas-poor major mergers, and show that the formation of slowly-rotating elliptical galaxies often requires a resolution that is beyond the present-day standards to be…
In order to specify cosmologically motivated initial conditions for major galaxy mergers (mass ratios $\leq$ 4:1) that are supposed to explain the formation of elliptical galaxies we study the orbital parameters of major mergers of cold…
We examine the origin of photometrical properties of N-body merger remnants from the perpective of their orbital content. We show that disc mergers alone are unlikely to form a boxy-discy dichotomy in isophotal shape, because of the…
The processes are investigated by which gas loses its angular momentum during the protogalactic collapse phase, leading to disk galaxies that are too compact with respect to the observations. High-resolution N-body/SPH simulations in a…
Modeling the Milky Way stellar halo requires well-determined density and velocity anisotropy profiles. However, it has been challenging to gather a large sample of stars with six-dimensional data that extend beyond 40 kpc to map the outer…
We analyse interacting galaxy pairs with evidence of tidal features in the Sloan Digital Sky Survey Data Release 7 (SDSS-DR7). The pairs were selected within $z<0.1$ by requiring a projected separation $r_p < 50 \kpc$ and relative radial…
Galaxy merging is the late time manifestation of the galaxy formation process and likely significantly effects $z<1$ galaxies. A ``maximum reasonable rate'' model for merging finds a $\sim2$ mag K band increase in the luminosities of dwarf…
Collisionless N-body simulations of merging disk-galaxies with mass ratios ($\eta$) of 1:1, 2:1, 3:1, and 4:1 have been performed using direct summation with the special purpose hardware GRAPE. The simulations are used to examine whether…
This paper provides two families of flexible and simple galaxy models. Representatives of many of the families possess the important cosmological cusps, with the density behaving like 1/r or 1/r^1.33 or 1/r^1.5 at small radii. The density…
We present the results of several detailed numerical N-body simulations of the dynamical interactions of two equal mass disc galaxies. Both galaxies are embedded in spherical halos of dark matter and contain central bulges. Our analysis of…
Early - type galaxies (ETGs) define a narrow strip in the size - mass plane because of the observed correlation between the effective radius $R_{eff}$ and the total stellar mass $M_{\star}$. When expressed in logarithmic units, a linear…
We investigate the dynamical evolution of hierarchical three-body systems under the effect of tides, when the ratio of the orbital semi-major axes is small and the mutual inclination is relatively large (greater than 20 degrees). Using the…
Aims:In this study we investigate the evolution of shape and kinematics of elliptical galaxies in a cosmological framework. Methods: We use a set of hydrodynamic, self-consistent simulations operating in the context of a concordance…
We investigate two possible effects of the tidal field induced by a spherical cluster on its elliptical galaxy members: the modification of the ellipticity of a spherical galaxy and the isophotal alignment in the cluster radial direction of…
Outward migration of low-mass planets has recently been shown to be a possibility in non-barotropic disks. We examine the consequences of this result in evolutionary models of protoplanetary disks. Planet migration occurs towards…
Recent high-precision observations with HST and Gaia enabled new investigations of the internal kinematics of star clusters (SCs) and the dependence of kinematic properties on the stellar mass. These studies raised new questions about the…
Galaxy mergers are a fundamental part of galaxy evolution. To study the resulting mass distributions of different kinds of galaxy mergers, we present a simulation suite of 36 high-resolution isolated merger simulations, exploring a wide…
Motion of stellar-mass satellites is studied around a massive compact body which is surrounded by a gaseous slab of a stationary accretion disc. The satellites suffer an orbital decay due to hydrodynamical interaction with the disc medium…