Related papers: Self-Consistent Evolution of Ring Galaxies
A possible connection among host-galaxies of gamma-ray bursts, BL Lacs and quasars is analysed. It is believed that the gamma-ray bursts, which do not show radio or infrared emission, occur in faint blue dwarf galaxies, that are seen around…
Blue stragglers are natural phenomena in star clusters. They originate through mass transfer in isolated binaries, as well as through encounters between two or more stars, in a complex interplay between stellar dynamics and stellar…
The galactic population of globular clusters are old, dense star systems, with a typical cluster containing $10^4 - 10^6$ stars. As an old population of stars, globular clusters contain many collapsed and degenerate objects. As a dense…
Spiral galaxies show axial symmetry and an intrinsic 2D-chirality. Environmental effects can influence the chirality of originally isolated stellar systems and a progressive loss of chirality can be recognised in the Hubble sequence. We…
To address the problem concerning the early formation of stars in massive galaxies, we present the results of a semi-analytic model of galaxy formation which includes a physical description of starbursts triggered by galaxy interactions.…
Recent observations indicate that the progenitors of globular clusters (GCs) at high redshifts had high average stellar surface densities above $10^5\, \mathrm{M}_\odot\, \mathrm{pc}^{-2}$. The internal structure and kinematics of the…
The relationship between star formation and infrared emission in galaxies will be investigated. If galaxies were simple objects and young stars were completely covered with dust, then all the absorbed light of the young stars would be…
RiGs are the result of the impact between two galaxies, with one of them passing close to the centre of the other, piercing its gaseous and stellar disc. In this framework, the impact generates a shock wave front that propagates within the…
We investigate the galaxy populations in seven X-ray selected, intermediate-redshift groups (0.2<z<0.6). Overall, the galaxy populations in these systems are similar to those in clusters at the same redshift; they have large fractions of…
Many evidences exist for a connection between galaxy interactions and induced star formation. However, a large range of responses of galaxies to tidal interactions is found, both in observations and in numerical simulations. We will discuss…
This chapter of the book Planetary Ring Systems addresses the origin of planetary rings, one of the least understood processes related to planet formation and evolution. Whereas rings seem ubiquitous around giant planets, their great…
The correspondence between galaxy major mergers and starburst activity is well-established observationally and in simulations of low redshift galaxies. However, the evolution of the properties of interactions and of the galaxies involved…
Over the last decades, numerous wide (>1000 AU) binaries have been discovered in the Galactic field and halo. The origin of these wide binaries cannot be explained by star formation or by dynamical interactions in the Galactic field. We…
Star-forming galaxies populate a main sequence (MS), a well-defined relation between stellar mass (M*) and star-formation rate (SFR). Starburst (SB) galaxies lie significantly above the relation whereas quenched galaxies lie below the…
To understand the processes that build up galaxies we investigate the stellar structure and gas kinematics of spiral and irregular galaxies out to redshift 1. We target 92 galaxies in four cluster (z = 0.3 & 0.5) fields to study the…
(Abridged) We interpret gamma ray bursts as relativistic, electromagnetic explosions. Specifically, we propose that they are created when a rotating, relativistic, stellar-mass progenitor loses much of its rotational energy in the form of a…
We study a cosmological scenario for gamma ray bursts (GRBs) where relativistic flows interact with dense radiation fields. It is shown that this scenario is plausible in very dense stellar regions which are known to exist in collapsed…
Globular clusters are collisional systems, meaning that the stars inside them interact on timescales much shorter than the age of the Universe. These frequent interactions transfer energy between stars and set up observable trends that tell…
We introduce a collection of primarily centrally star-forming galaxies that are selected by disk color to have truncated disk star formation. We show that common explanations for centrally-concentrated star formation -- low stellar mass,…
The duration of a starburst is a fundamental parameter affecting the evolution of galaxies yet, to date, observational constraints on the durations of starbursts are not well established. Here we study the recent star formation histories…