Related papers: Ejection of Supernova-Enriched Gas From Dwarf Disk…
There is increasing evidence that low mass stars with circumstellar disks can be born close to massive stars, in some cases within tenths of a pc. If the disks have lifetimes greater than those of the more massive stars, they are exposed to…
Many theoretical studies have shown that external photoevaporation from massive stars can severely truncate, or destroy altogether, the gaseous protoplanetary discs around young stars. In tandem, several observational studies report a…
Gas giants' early ($\lesssim 5$ Myr) orbital evolution occurs in a disc losing mass in part to photoevaporation driven by high energy irradiance from the host star. This process may ultimately overcome viscous accretion to disperse the disc…
We construct one dimensional steady-state models of accretion disks produced by the tidal disruption of a white dwarf (WD) by a neutron star (NS) or stellar mass black hole (BH). At radii r <~ 1e8.5-1e9 cm the midplane density and…
Strong inflows of gas from the outer disk to the inner kiloparsecs are induced during the interaction of disk galaxies. This inflow of relatively low-metallicity gas dilutes the metallicity of the circumnuclear gas. We have investigated…
We calculate the ionisation fraction in protostellar disk models using two different gas-phase chemical networks, and examine the effect of turbulent mixing by modelling the diffusion of chemical species vertically through the disk. The aim…
We investigate the formation and evolution of dwarf galaxies in a high resolution, hydrodynamical cosmological simulation of a Milky Way sized halo and its environment. Our simulation includes gas cooling, star formation, supernova…
A model of supernovae feedback during disc galaxy formation is developed. The model incorporates infall of cooling gas from a halo and outflow of hot gas from a multiphase interstellar medium and a self-regulated model for star formation.…
We present self-consistent models of gas in optically-thick dusty disks and calculate its thermal, density and chemical structure. The models focus on an accurate treatment of the upper layers where line emission originates, and at radii…
Eruptive mass loss in massive stars is known to occur, but the mechanism(s) are not yet well-understood. One proposed physical explanation appeals to opacity-driven super-Eddington luminosities in stellar envelopes. Here, we present a 1D…
We investigate the effect of ionising radiation from Massive Young Stellar Objects impinging on their emerging spectral energy distribution. By means of detailed radiative transfer calculations including both the gaseous and dust phase of…
The destiny of planetary systems through the late evolution of their host stars is very uncertain. We report a metal-rich gas disk around a moderately hot and young white dwarf. A dynamical model of the double-peaked emission lines…
We update the treatment of chemical evolution in the Munich semi-analytic model, L-GALAXIES. Our new implementation includes delayed enrichment from stellar winds, supernovae type II (SNe-II) and supernovae type Ia (SNe-Ia), as well as…
Nova explosions occur on accreting white dwarfs. A thermonuclear runaway in the H-rich accreted envelope causes its ejection without destroying the white dwarf, and an increase in the luminosity by several magnitudes. Accretion is…
We study the global efficiency of star formation in high resolution hydrodynamical simulations of gas discs embedded in isolated early-type and spiral galaxies. Despite using a universal local law to form stars in the simulations, we find…
We use the most extensive integral field spectroscopic map of a local galaxy, NGC 628, combined with gas and stellar mass surface density maps, to study the distribution of metals in this galaxy out to 3 effective radii ($\rm R_e$). At each…
We analyse N-body simulations of star-forming regions to investigate the effects of external far and extreme ultra-violet photoevaporation from massive stars on protoplanetary discs. By varying the initial conditions of simulated…
In recent years, the number of white dwarfs (WDs) showing infrared (IR) excesses, attributed to circumstellar dust disks, has grown significantly. Gaseous disks have also been detected in some WDs with dust. We obtained optical spectra with…
Here we investigate an exemplary chemodynamical evolutionary simulation of a dwarf irregular galaxy. By means of this model we demonstrate the existence of three gas mixing cycles: 1) An inner "local cycle" mixing the metals produced in…
After the stars of a new, embedded star cluster have formed they blow the remaining gas out of the cluster. Especially winds of massive stars and definitely the on-set of the first supernovae can remove the residual gas from a cluster. This…