Related papers: An Extended, Physically Calibrated FP for Elliptic…
Current theory of disk galaxy formation is used to study fundamental-plane (FP) type of relations for disk galaxies. We examine how the changes in model parameters affect these relations and explore the possibility of using such relations…
Based on a uniform dynamical analysis of line-profile shapes for 21 luminous round elliptical galaxies, we have investigated the dynamical family relations of ellipticals: (i) The circular velocity curves (CVCs) of elliptical galaxies are…
Cosmic shear holds great promise for a precision independent measurement of $\Omega\rm_m$, the mass density of the universe relative to the critical density. The signal is expected to be weak, so a thorough understanding of systematic…
We present a systematic analysis of the constraints $\sigma_\gamma$ on the mass profile slope $\gamma$ obtainable when fitting a singular power-law ellipsoid model to a typical strong lensing observation of an extended source. These results…
Motivated by present indirect evidences that galaxies are surrounded by dark matter halos, we investigate whether their physical properties can be described by a formulation of the virial theorem which explicitly takes into account the…
Modified Newtonian equations for gravitational orbits in the expanding universe indicate that local gravitationally bounded systems like galaxies and planetary systems are unaffected by the expansion of the Universe. This result is derived…
We derive the average mass profile of elliptical galaxies from the ensemble of 161 strong gravitational lens systems selected from several surveys, assuming that the mass profile scales with the stellar mass and effective radius of each…
Various models of modified gravity invoke ``screening'' mechanisms that are sensitive to the value of the local gravitational potential. This could have observable consequences for galaxies. These consequences might be seen by comparing two…
We develop a parameterized post-Friedmann (PPF) framework which describes three regimes of modified gravity models that accelerate the expansion without dark energy. On large scales, the evolution of scalar metric and density perturbations…
The theory of the Clausius' virial maximum to explain the Fundamental Plane (FP) proposed by Secco (2000, 2001,2005) is based on the existence of a maximum in the Clausius' Virial (CV) potential energy of a early type galaxy (ETG) stellar…
This article reviews the popular reasons for the belief that dwarf elliptical galaxies and (ordinary) elliptical galaxies are distinct and separate species. They include: light-profile shape (or similarly image concentration); the…
Three observables of early-type galaxies - size ($r_{e}$), surface brightness ($I_{e}$), and velocity dispersion ($\sigma_{0}$) - form a tight planar correlation known as the fundamental plane (FP), which has provided great insights into…
In this paper we present a quantitative analysis of the chemical abundances in "monolithic" N-body-Tree-SPH models of elliptical galaxies to determine whether the ratio [alpha/Fe] increases with the galaxy mass as suggested by observational…
Assuming spherical symmetry and dynamical equilibrium within a given gravitational potential, a dwarf spheroidal (dSph) galaxy's globally averaged stellar velocity dispersion depends entirely on the shape of its stellar density profile.…
Observations indicate that the baryonic matter of galaxies is surrounded by vast dark matter halos, which nature remains unknown. This document details the analysis of the results published in MNRAS 438, 2, 1535 (2014) reporting an…
We suggest the radii and luminosities of the X-ray emitting halos of elliptical galaxies define a fundamental plane with the star velocity dispersions, as for the corresponding optical observables. Since the X-ray emitting material usually…
Subject of this paper are the statistical properties of ellipticity alignments between galaxies evoked by their coupled angular momenta. Starting from physical angular momentum models, we bridge the gap towards ellipticity correlations,…
We describe galaxy surface photometry based on fitting ellipses to the isophotes of the galaxies. Example galaxies with different isophotal shapes are used to illustrate the process, including how the deviations from elliptical isophotes…
We seek to understand the impact on shape estimators obtained from circular and elliptical shapelet models under two realistic conditions: (a) only a limited number of shapelet modes is available for the model, and (b) the intrinsic…
Lacking the ability to follow individual galaxies on cosmological timescales, our understanding of individual galaxy evolution is broadly inferred from population trends and behaviours. In its most prohibitive form, this approach assumes…