相关论文: Dissipation and Extra Light in Galactic Nuclei: II…

Shells in Elliptical Galaxies are faint, sharp-edged features, believed to provide evidence of a recent ($\sim 0.5 - 2 \times 10^9$ years ago) merger event. We analyse the Globular Cluster (GC) systems of six shell elliptical galaxies, to…

We show, using the N-body code GADGET-2, that stellar scattering by massive clumps can produce exponential discs, and the effectiveness of the process depends on the mass of scattering centres, as well as the stability of the galactic disc.…

We report on SPT-CLJ2011-5228, a giant system of arcs created by a cluster at $z=1.06$. The arc system is notable for the presence of a bright central image. The source is a Lyman Break galaxy at $z_s=2.39$ and the mass enclosed within the…

Far-infrared Spitzer observations of elliptical galaxies are inconsistent with simple steady state models of dust creation in red giant stars and destruction by grain sputtering in the hot interstellar gas at T ~ 10^7 K. The flux at 24…

We describe photometry at mid-infrared passbands (1.2 - 24 microns) for a sample of 18 elliptical galaxies. All surface brightness distributions resemble de Vaucouleurs profiles, indicating that most of the emission arises from the…

We present a new set of dissipationless N-body simulations to examine the feasibility of creating bright ellipticals (following the Kormendy relation) by hierarchically merging present-day early-type dwarf galaxies, and to study how the…

Scattering of stars by interstellar clouds or massive clumps increases the stellar velocity dispersion and promotes a radial disk profile that is exponential. Here we show that such scattering reaches a steady-state distribution function of…

We present an analysis of the central cusp slopes and core parameters of early-type galaxies using a large database of surface brightness profiles obtained from Hubble Space Telescope observations. We examine the relation between the…

Scaling relations are fundamental tools for exploring the morphological properties of galaxies and understanding their formation and evolution. Typically, galaxies follow a scaling relation between mass and size, measured by effective…

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…

We present results from our Very Large Telescope large program to study the dynamical evolution of local Ultraluminous Infrared Galaxies (ULIRGs) and QSOs. This paper is the second in a series presenting the stellar kinematics of 54 ULIRGs,…

Luminosity Functions have been obtained for very faint dwarf galaxies in the cores of four rich clusters of galaxies (Abell 2052, 2107, 2199 and 2666). It is found that the luminosity function of dwarf galaxies rises very steeply in these…

We present here the first study of the X-ray properties of an evolutionary sample of merging galaxies. Both ROSAT PSPC and HRI data are presented for a sample of eight interacting galaxy systems, each believed to involve a similar encounter…

In models of galaxy formation in a hierarchical Universe, elliptical galaxies form through the merging of smaller disk systems. These models yield a number of testable predictions if reliable techniques for determining the relative ages and…

It has been suggested that merging plays an important role in the formation and the evolution of elliptical galaxies(EGs). In order to understand the past merging history of EGs, we studied the optical-NIR color gradients of 204 EGs. The…

Merger remnants of small groups of galaxies are contrasted with relics of mergers of pairs of galaxies to determine which process produces objects that best compare to real ellipticals. In both cases, the progenitors consist of…

We assemble a statistical set of global mass models for ~2,000 nearly spherical SDSS galaxies at a mean redshift of 0.12 based on their aperture velocity dispersions and newly derived luminosity profiles in conjunction with published…

Sersic parameters characterising the density profiles of remnants formed in collision-less disc galaxy mergers are obtained; no bulge is included in our simulations. For the luminous component we find that the Sersic index is n ~ (1.5,5.3)…

Central cluster galaxies in cooling flows show the signatures of gaseous accretion and ongoing star formation at rates ranging between 1-100 solar masses per year. Their blue morphologies usually reflect the low net angular momentum content…

Using photometric and redshift data for the Virgo and Coma clusters, we present evidence for a correlation between the light concentration of elliptical galaxies (including dwarf ellipticals) and the local 3-D (i.e. non-projected) density…