Related papers: Gas in Shearing Density Waves
In our current interpretation of the hierarchical structure of the universe it is well established that galaxies collide and merge with each other during their lifetime. If massive black holes (MBHs) reside in galactic centres, we expect…
We show the initial results of our 3D MHD simulations of the flow of the Galactic atmosphere as it responds to a spiral perturbation in the potential. In our standard case, as the gas approaches the arm, there is a downward converging flow…
In the standard paradigm of galaxy formation and evolution, the baryonic component of galaxies forms from the collapse and condensation of gas within dark matter haloes, and later grows from continuous accretion of gaseous mass, both in…
The arm structure of the Milky Way remains somewhat of an unknown, with observational studies hindered by our location within the Galactic disc. In the work presented here we use smoothed particle hydrodynamics (SPH) and radiative transfer…
We begin by recalling the isothermal, collisionless, disc-halo. The disc component is the Mestel disc. Subsequently we introduce spiral arms to such an isothermal disc-halo system that are co-moving in the mean with an axi-symmetric…
Theoretically, inflowing filaments of gas are one of the main causes of growth for a galaxy. Nonetheless, observationally, probing ongoing gas accretion is challenging. As part of the Gas Stripping Phenomena in galaxies with MUSE (GASP)…
This thesis investigates the dynamical effect of two structural components of disk galaxies, namely, the dark matter halo and the interstellar gas on the origin and persistence issue of spiral structure in disk galaxies through theoretical…
Using an equation of motion for a self-gravitating filament, we show how galactic spiral arms might be created and sustained. We find that the combination of differential rotation of the galactic disk and the self-gravity of the arm (as…
When a massive object crosses a star stream velocity changes are induced both along and transverse to the stream which can lead to the development of a visible gap. For a stream narrow relative to its orbital radius the time of stream…
We investigate the possibility of describing the spiral pattern of the Milky Way in terms of a model of superposition 2- and 4-armed wave harmonics (the simplest description, besides pure modes). Two complementary methods are used: a study…
Galaxy disks evolve through angular momentum transfers between sub-components, like gas, stars, or dark matter halos, through non axi-symmetric instabilities. The speed of this evolution is boosted in presence of a large fraction of cold…
We investigate both analytically and numerically the motion of massless particles orbiting primary star in a close circular binary system with particular focus on the gas drag effects. These are the first calculations with particles ranging…
Understanding how the large-scale kinematics of the MW shape the formation and evolution of the interstellar medium remains challenging from an observational perspective, and numerical models that can reproduce the observed structure and…
I review the progress of SPH calculations for modelling galaxies, and resolving gas dynamics on GMC scales. SPH calculations first investigated the response of isothermal gas to a spiral potential, in the absence of self gravity and…
We have undertaken numerical simulations of galaxy interactions and mergers, coupling the dynamics with the star formation history and the chemical evolution. The self-gravity of stars and gas is taken into account through a tree-code…
Spiral galaxies are observed to exhibit a range of morphologies, in particular in the shape of spiral arms. A key diagnostic parameter is the pitch angle, which describes how tightly wound the spiral arms are. Observationally and…
We numerically study the origin of the multi-armed spiral structure observed in the circumnuclear gaseous mini-disks of nearby galaxies. We show that the presence of dust in such disks and its interaction with the gravitationally stable…
Holes and clumps in the interstellar gas of dwarf irregular galaxies are gravitational scattering centers that heat field stars and change their radial and vertical distributions. Because the gas structures are extended and each stellar…
We use high resolution simulations to study the formation and distribution of galaxies within a cluster which forms hierarchically. We follow both dark matter and baryonic gas which is subject to thermal pressure, shocks and radiative…
By combining two surveys covering a large fraction of the molecular material in the Galactic disk we investigate the role the spiral arms play in the star formation process. We have matched clumps identified by ATLASGAL with their parental…