相关论文: The Connection between Orbits and Isophotal Shape …
The discovery of proto-globular cluster candidates in many current-day mergers allows us to better understand the possible effects of a merger event on the globular cluster system of a galaxy, and to foresee the properties of the…
We search for signatures of recent galaxy close interactions and mergers in a sample of 202 early-type galaxies in the local universe from the public SDSS Stripe82 deep images ($\mu_r \sim 28.5$ mag arcsec$^{-2}$). Using two different…
We recently revealed that bulges and elliptical galaxies broadly define distinct, super-linear relations in the $M_{\rm bh}$-$M_{\rm *,sph}$ diagram, with the order-of-magnitude lower $M_{\rm bh}/M_{\rm *,sph}$ ratios in the elliptical…
Morphogenesis emerges from dynamic feedback among geometry, mechanics, and chemistry; however, disentangling these contributions in living systems remains challenging. Here, we focus on the interplay between geometry and mechanics by…
In hierarchical models of galaxy formation, ellipticals form from the merging of disk galaxies drawn together by gravity as their surrounding dark halos coalesce. Using semi-analytic techniques, we are able to follow the merging, star…
The structural properties of elliptical galaxies are consistent with their formation in a merging hierarchy. In this picture, the role of gaseous processes and dissipation decreased with increasing mass creating preferentially rotationally…
The flat stellar density cores of massive elliptical galaxies form rapidly due to sinking supermassive black holes (SMBH) in gas-poor galaxy mergers. After the SMBHs form a bound binary, gravitational slingshot interactions with nearby…
We investigate the shape and morphology of early-type galaxies (ETGs) within the framework of Modified Newtonian Dynamics (MOND). Building on our previous studies, which demonstrated that the monolithic collapse of primordial gas clouds in…
We investigate the problem of determining the shape of a rotating celestial object - e.g., a comet or an asteroid - under its own gravitational field. More specifically, we consider an object symmetric with respect to one axis - such as a…
We discuss the problem of using stellar kinematics of early-type galaxies to constrain the galaxies' orbital anisotropies and radial mass profiles. We demonstrate that compressing a galaxy's light distribution along the line of sight…
(Abridged) The structural parameters of a magnitude-limited sample of 148 unbarred S0-Sb galaxies were analyzed to derive the intrinsic shape of their bulges. We developed a new method to derive the intrinsic shape of bulges based on the…
We use N-body simulations to study the formation of rings in a disc galaxy by the impact of a small spherical companion. Both barred and nonbarred target discs are considered. We discuss the effect of the properties of the target disc…
We present the results of a self-consistent $N$-body simulation following the evolution of a primordial population of thick disc globular clusters (GCs). We study how the internal properties of such clusters evolve under the action of…
We present an investigation of galaxy-galaxy interactions and their effects on the velocity fields of disc galaxies in combined N-body/hydrodynamic simulations, which include cooling, star formation with feedback, and galactic winds.…
We use numerical models which include star formation to analyze the mass profiles of remnants formed by mergers of disk galaxies. During a merger, dissipation in gas and ensuing star formation leave behind a dense stellar core in the…
Based on Morse theory for the energy functional on path spaces we develop a deformation theory for mapping spaces of spheres into orthogonal groups. This is used to show that these mapping spaces are weakly homotopy equivalent, in a stable…
We present a two-dimensional kinematic analysis for a sample of simulated binary disc merger remnants with mass ratios 1:1 and 3:1. For the progenitor discs we used pure stellar models as well as models with 10% of their mass in gas. A…
The shapes of galaxies, in particular their outer regions, are important guideposts to their formation and evolution. Here we report on the discovery of strongly box-shaped morphologies of the, otherwise well-studied, elliptical and…
We present multi-component photometric decompositions of $r$-band Hyper Suprime-Cam images for a sample of 75 edge-on massive compact galaxies (MCGs) at $z < 0.1$, selected as $+2\sigma$ outliers in the stellar mass-velocity dispersion…
We present a detailed study of rotational asymmetry in galaxies for both morphological and physical diagnostic purposes. An unambiguous method for computing asymmetry is developed, robust for both distant and nearby galaxies. By degrading…