Related papers: Gravitational Heating Helps Make Massive Galaxies …
We calculate the number density and the energy density of a massive scalar particle conformally coupled to gravity produced by gravitational particle creation in the case the kination stage follows inflation. In this model, mode functions…
The cosmic star formation rate density first increases with time towards a pronounced peak 10 Gyrs ago (or z=1-2) and then slows down, dropping by more than a factor 10 since z=1. The processes at the origin of the star formation quenching…
A scenario of galaxy formation is put forward which is a process of sudden condensation just after recombination. It is essentially based on the fact that the cosmic matter gas after recombination is a general relativistic Boltzmann gas…
We use cosmological simulations to study a characteristic evolution pattern of high redshift galaxies. Early, stream-fed, highly perturbed, gas-rich discs undergo phases of dissipative contraction into compact, star-forming systems (blue…
In conventional models of galactic and cluster cooling flows widespread cooling (mass dropout) is assumed to avoid accumulation of unacceptably large central masses. However, recent XMM observations have failed to find spectral evidence for…
We study the formation of hot spheroidal systems within the frame of a scenario where galaxy formation and evolution is related to the gentle mass aggregation history and primordial angular momentum of protogalaxies, both defined by the…
The simple reading of the evidence is that the large elliptical galaxies existed at about the present star mass and comoving number density at redshift z=2. This is subject to the usual uncertainties of measurement and interpretation in…
We investigate the spatial, kinematic and chemical properties of globular cluster systems formed in merging and interacting galaxies using N-body/SPH simulations. Although we can not resolve individual clusters in our simulation, we assume…
Radiative cooling may plausibly cause hot gas in the centre of a massive galaxy, or galaxy cluster, to become gravitationally unstable. The subsequent collapse of this gas on a dynamical timescale can provide an abundant source of fuel for…
The universe's largest galaxies reside at the centers of galaxy clusters and are embedded in hot gas that, if left unchecked, would cool prodigiously and create many more new stars than are actually observed. Cooling can be regulated by…
Utilizing high-resolution large-scale galaxy formation simulations of the standard cold dark matter model, we examine global trends in the evolution of galaxies due to gravitational shock heating by collapse of large halos and large-scale…
We initiate a study of the gravitational-wave signatures of a phase transition that occurs as the Universe's temperature increases during reheating. The gravitational-wave signatures of such a heating phase transition are different from…
We present detailed spatially resolved measurements of the thermodynamic properties of the X-ray emitting gas in the inner regions of the five nearest, X-ray and optically brightest, and most X-ray morphologically relaxed giant elliptical…
In the absence of galactic winds, the rate at which gas accretes onto galaxies is determined by the gravitational potential and by radiative cooling. However, outflows driven by supernovae and active galactic nuclei not only eject gas from…
Observed rotation curves in star-forming galaxies indicate a puzzling dearth of dark matter in extended flat cores within haloes of mass $\geq\! 10^{12}M_\odot$ at $z\!\sim\! 2$. This is not reproduced by current cosmological simulations,…
We present for smooth non-oscillating backgrounds an analytic formula which calculates the energy density of massive and massless particles created via gravitational particle production, thus giving the corresponding reheating temperature.…
Star formation in the universe's most massive galaxies proceeds furiously early in time but then nearly ceases. Plenty of hot gas remains available but does not cool and condense into star-forming clouds. Active galactic nuclei (AGN)…
Galaxy evolution reveals itself not only through the evolving properties of galaxies themselves but also through its impact on the surrounding environment. The intergalactic medium in particular holds a fossil record of past galaxy…
Dwarf galaxies provide a special environment due to their low mass, small size and generally low metal content. These attributes make them perfect laboratories for the interaction of massive stars with the interstellar medium on small and…
We introduce a toy model that describes (in a single equation) the mass in stars as a function of halo mass and redshift. Our model includes the suppression of gas accretion from gravitational shock heating and AGN jets mainly for M_halo >…