Special Issue "Advances in Our Understanding of the Dynamics of Galaxies"
A special issue of Galaxies (ISSN 2075-4434).
Deadline for manuscript submissions: closed (31 December 2013)
Prof. Dr. Peter J. Quinn
The steady-state internal dynamics of stellar systems, the linear and non-linear development of large scale structure and the processes associated with galaxy formation and collisions, have been at the heart of modern astrophysics for the past 100 years. Despite the development of beautiful mathematical formalisms and the application of power computational techniques and algorithms, we are still faced with a number of challenges to our understanding of the current structure and evolution of galaxies. Why do the rotation curves of late-type spirals imply large dark matter halo core radii in apparent disagreement with CDM simulations? How much substructure is there in dark matter halos of galaxies and does it change with time? Is the angular momentum content and distribution of observed spiral disks consistent with the tidal-torquing paradigm? Are isolated disk galaxies stable and is the structure and formation of spiral bulges consistent with an encounter-free environment? Do velocity fields in elliptical galaxies contain clues to their formation process? Do we really understand polar disks around some spirals and what are they telling us about dark matter? All of these questions are largely unanswered and present significant challenges and opportunities. They may also probe the interface of dynamical and hydrodynamical processes in galaxy formation and evolution - an interface that can be constrained by a complete appreciation of the dynamical processes involved. This special volume is intended to outline our current level of understanding and our current dilemmas in applying dynamics to the origin and evolution of galaxies.
Prof. Dr. Peter J. Quinn
Manuscript Submission Information
Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.
Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Galaxies is an international peer-reviewed open access quarterly journal published by MDPI.
Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 350 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.
- galaxy dynamics
- dark matter
- galaxy formation and evolution
- structure formation
- linear and non-linear dynamical processes in galaxies and the Universe
- luminous and non-luminous galaxy structures
The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.
Type of Paper: Review
Title: The Dynamics of Nuclear Activity
Author: Carole Mundell
Abstract: For many decades, the study of the physics of active galactic nuclei (AGN) and the properties of galaxies were mutually exclusive. Nowadays, AGN are recognized as an integral to galaxy formation and evolution, and the end products of quasars—supermassive black holes—are accepted to be unibiquitous in all bulge dominated galaxies today. A key unsolved problem, however, is what causes nuclear activity and what is the role of the host galaxy dynamics? Here I will provide a brief historical perspective and a broad overview of the contribution made by statistical studies using large samples, e.g., from the SDSS, before concentrating on a range of detailed studies of the stellar and gaseous kinematics of active and quiescent galaxies. In addition to the distribution of gas and stars in nearby galaxies, "3-D" studies allow the kinematics of molecular, neutral and ionized gas and stars to be mapped on ever smaller scales towards the central black hole, for comparison with theoretical predictions. I will highlight the importance of 3D studies at optical, radio and mm wavelengths and particularly the importance of studying the inner kiloparsec, where activity and dynamical timescales become comparable. The ultimate goal of such studies is to discover the physical mechanisms that trigger and fuel nuclear activity.
Type of Paper: Review
Title: Formation and Evolution of Early-Type Galaxies
Author: Cesare Chiosi and Emiliano Merlin
Abstract: In this review, we present some recent results for NB-TSPH models of early type galaxies (ETGs) made of Dark and Baryonic matter according to the -CDM model of the Universe. The models are framed in the quasi-monolithic or early hierarchical scenario. By means of fully hydrodynamical NB-TSPH simulations performed with the Padova code EVOL, we produce a number of self-similar models of ETGs for different initial total masses and over-densities with respect to the surrounding medium, and follow their evolution from the detachment from the linear regime and Hubble flow at z ≥ 20 down to the stage of
nearly complete assembly of the stellar content (at about z ≤ 1 for all of them) and often to the present epoch (z = 0). We find a strong correlation between the total mass and/or over-density of the proto-haloes and the subsequent star formation histories (SFH). Massive (Mtot ≃ 1013M⊙) haloes experience a single, intense burst of star formation (with rates ≥ 103M⊙/yr) at early epochs, consistently with observations, with a weak dependence on the initial over-density; intermediate mass (Mtot ≃ 1011M⊙) haloes have histories that strongly depend on their initial over-density; finally, low mass haloes (Mtot ≃ 109M⊙) always have erratic, burst-like star forming histories. The model galaxies have morphological, structural, and chemical properties resembling those of real galaxies. In addition to this, we try to cast light on the physical causes of the tight correlation between the mass in stars and the size of ETGs (the Mass-Radius Relation, MRR). We suggest that the MRR is the result of two complementary mechanisms: on one hand, the result of local physical processes, which fix the star mass and the radius of individual objects; on the other hand, the action of cosmological global, statistical principles, which shape the distribution of objects in the MR-plane. In the picture emerging from this study, nature seems to play the dominant role, whereas nurture has a secondary importance.