Related papers: Pattern Speeds and Galaxy Morphology
The evolution of masses and sizes of passive (early-type) galaxies with redshift provides ideal constraints to galaxy formation models. These parameters can in principle be obtained for large galaxy samples from multi-band photometry alone.…
It was recently observed that sand flowing down a vertical tube sometimes forms a traveling density pattern in which a number of regions with high density are separated from each other by regions of low density. In this work, we consider…
We invoke the estimates of the amplitudes of the velocity perturbations $f_R$ and $f_\theta$ caused by the influence of a spiral density wave that have been obtained by us previously from three stellar samples. These include Galactic masers…
High resolution gravity plus smoothed particle hydrodynamics simulations are used to study the formation of galaxies within the context of hierarchical structure formation. The simulations have sufficient dynamic range to resolve from ten…
The theoretical understanding of density waves in disk galaxies starts from the classical WKB perturbative analysis of tight-winding perturbations, the key assumption being that the potential due to the density wave is approximately radial.…
Galactic bars are found in the majority of disc galaxies. They rotate nearly rigidly with an angular frequency called pattern speed. Previous idealised simulations have shown that bar pattern speed decreases with time due to dynamical…
The morphology of a galaxy stems from secular and environmental processes during its evolutionary history. Thus galaxy morphologies have been a long used tool to gain insights on galaxy evolution. We visually classify morphologies on…
The diversity of galaxy morphologies and their relations with galaxy and halo properties is fundamental to understanding galaxy formation. Cosmological simulations of representative volumes can help disentangle the origin of observed…
Galaxy morphologies and star-formation rates depend on environment. Galaxies in under-dense regions are generally star-forming and disky whereas galaxies in overdense regions tend to be early-type and not actively forming stars. The…
In this article, we present a galactic gravitational model of three degrees of freedom (3D), in order to study and reveal the character of the orbits of the stars, in a binary stellar system composed of a primary quiet or active galaxy and…
We study gravitational instability and consequent star formation in a wide range of isolated disk galaxies, using three-dimensional, smoothed particle hydrodynamics simulations at resolution sufficient to fully resolve gravitational…
In both observed and simulated galaxies, disk morphologies become more prevalent at higher masses and lower redshifts. To elucidate the physical origin of this trend, we develop a simple analytical model in which galaxy morphology is…
One of the main problems of observational cosmology is to determine the range in which a reliable measurement of galaxy correlations is possible. This corresponds to determine the shape of the correlation function, its possible evolution…
We study the behaviour of interacting self-propelled particles, whose self-propulsion speed decreases with their local density. By combining direct simulations of the microscopic model with an analysis of the hydrodynamic equations obtained…
We provide a physical interpretation and explanation of the morphology-density relation for galaxies, drawing on stellar masses, star formation rates, axis ratios and group halo masses from the Sloan Digital Sky Survey. We first re-cast the…
Gaia DR2 has delivered full-sky 6-D measurements for millions of stars, and the quest to understand the dynamics of our Galaxy has entered a new phase. Our aim is to reveal and characterize the kinematic sub-structure of the different…
Detection of bending waves is a highly challenging task even in nearby disc galaxies due to their sub-kpc bending amplitudes. However, simulations show that the harmonic bending of a Milky Way like disc galaxy is associated with a harmonic…
Clues to the origins and evolution of our Galaxy can be found in the kinematics of stars around us. Remnants of accreted satellite galaxies produce over- densities in velocity-space, which can remain coherent for much longer than spatial…
The present work is devoted to study the dynamical evolution of the galaxies in scalar-GaussBonnet gravity in relationship with the MOND paradigm. This study is useful for giving meaning to the presence of a new gravitational constant. The…
Peculiar velocities are the motions of galaxies due to the gravitational influence of large-scale structure, and thus are an important cosmological probe of the underlying matter density field. In recent years the number of surveys designed…