相关论文: Radialization of satellite orbits in galaxy merger…
For a rigid model satellite, Chandrasekhar's dynamical friction formula describes the orbital evolution quite accurately, when the Coulomb logarithm is chosen appropriately. However, it is not known if the orbital evolution of a real…
We investigated the orbital evolution of satellite galaxies using numerical simulations. It has been long believed that the orbit suffers circularization due to the dynamical friction from the galactic halo during orbital decay. This…
A fully analytical formulation is developed to make dynamical friction modeling more realistic. The rate for a satellite to decay its orbit in a host galaxy halo is often severely overestimated when applying ChandraSekhar's formula without…
We have carried out a set of self-consistent N-body simulations to study the interaction between disc galaxies and merging satellites with the aim of determining the disc kinematical changes induced by such events. We explore a region of…
How fast a satellite decays its orbit depends on how slowly its mass is lost by tide. Motivated by inner halo satellite remnants like the Sgr and Omega Cen, we develop fully analytical models to study the orbital decay and tidal massloss of…
The main goal of this paper is to set up a numerical laboratory for the study of the slow evolution of the density and of the pressure tensor profiles of an otherwise collisionless stellar system, as a result of the interactions with a…
We study the dynamical evolution of a satellite orbiting outside of a companion spherical galaxy. The satellite is subject to a back-reaction force resulting from the density fluctuations excited in the primary stellar system. We evaluate…
We study the dynamical response of extended systems, hosts, to smaller systems, satellites, orbiting around the hosts using extremely high-resolution N-body simulations with up to one billion particles. This situation corresponds to minor…
Using analytic calculations and N-body simulations we show that in constant density (harmonic) cores, sinking satellites undergo an initial phase of very rapid (super-Chandrasekhar) dynamical friction, after which they experience no…
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…
The orbital properties of infalling satellite halos set the initial conditions which control the subsequent evolution of subhalos and the galaxies that they host, with implications for mass stripping, star formation quenching, and merging.…
We use N-body simulations to explore the influence of orbital eccentricity on the dynamical evolution of star clusters. Specifically we compare the mass loss rate, velocity dispersion, relaxation time, and the mass function of star clusters…
The evolution of a small satellite inside a more massive truncated isothermal spherical halo is studied using both the Theory of Linear Response for dynamical friction and N-Body simulations. The analytical approach includes the effects of…
Using test particle simulations we examine the structure of the outer Galactic disk as it is perturbed by a satellite in a tight eccentric orbit about the Galaxy. A satellite of mass a few times 10^9 Msol can heat the outer Galactic disk,…
In the framework of the fluctuation-dissipation approach to dynamical friction, we derive an expression giving the orbital energy exchange experienced by a compound body as it moves interacting with a non homogeneous discrete background.…
Central galaxies (CGs) in galaxy groups and clusters are believed to form and assemble a good portion of their stellar mass at early times, but they also accrete significant mass at late times via galactic cannibalism, that is merging with…
We analyse how drag forces modify the orbits of objects moving through extended gaseous distributions. We consider how hydrodynamic (surface area) drag forces and dynamical friction (gravitational) drag forces drive the evolution of orbital…
We use the Chandrasekhar formalism and direct N-body simulations to study the effect of dynamical friction on a test object only slightly more massive than the field stars, orbiting a spherically symmetric background of particles with a…
We use N-body simulations to study the infall of dark matter haloes onto rich clusters of galaxies. After identification of all cluster progenitors in the simulations, we select those haloes which accrete directly onto the main cluster…
We further investigate the long-term evolution of a trajectory of a stellar-mass orbiter which is gravitationally bound to a massive central body. The orbiter undergoes repetitionary collisions with an accretion disc. We consider eccentric…