We have performed hydrodynamic simulations of galaxy formation in a cold dark matter (ΛCDM) universe. We have followed galaxy formation in a dark matter halo, chosen to have a relatively quiet recent merger history, using different models for star formation and feedback. In all cases, we have adopted a multi-phase description of the interstellar medium and modelled star formation in quiescent a...

The inverse stellar structure problem determines the equation of state of the matter in stars from a knowledge of their macroscopic observables (e.g. their masses and radii). This problem was solved in a previous paper by constructing a spectral representation of the equation of state whose stellar models match a prescribed set of macroscopic observables. This paper improves and extends that wo...

We consider extended starlike networks where the hub node is coupled with several chains of nodes representing star rays. Assuming that nodes of the network are occupied by nonidentical self-oscillators we study various forms of their cluster synchronization. Radial cluster emerges when the nodes are synchronized along a ray, while circular cluster is formed by nodes without immediate connectio...

The inverse stellar structure problem determines the equation of state of the matter in stars from a knowledge of their macroscopic observables (e.g. their masses and radii). This problem was solved in a previous paper by constructing a spectral representation of the equation of state whose stellar models match a prescribed set of macroscopic observables. This paper improves and extends that wo...

Long-slit echelle spectra reveal bright extended emission from the K i λ7699 resonance line in the reflection nebula surrounding the extreme red supergiant VY Canis Majoris. The central star has long been known for its unusually-bright K i emission lines, but this is the first report of intrinsic emission from K i in the nebula. The extended emission is not just a reflected spectrum of the star...

We report the detection of spatially-extended mid-infrared emission around the luminous embedded star IRc9 in OMC-1, as seen in 8.8, 11.7, and 18.3 μm images obtained with T-ReCS on Gemini South. The extended emission is asymmetric, and the morphology is reminiscent of warm dust disks around other young stars. The putative disk has a radius of roughly 1. 5 (700 AU), and a likely dust mass of al...

Star formation rate (SFR) distributions of galaxies are often assumed to be bimodal with modes corresponding to star-forming and quiescent galaxies, respectively. Both classes of galaxies are typically studied separately, and SFR distributions of star-forming galaxies are commonly modelled as lognormals. Using both observational data and results from numerical simulations, I argue that this div...

The circumstellar structure of R Hydrae has been investigated in the IRAS survey scan data. R Hya is a late Mtype Mira variable star whose IRAS LRS spectrum is classified as 15 (no feature). But, it shows a remarkable infrared excess in the IRAS photometric data, which cannot be explained by an oxygen-rich circumstellar dust envelope of a mass losing latetype star without showing a significant ...

IRAS 06562−0337 has been the recent subject of a classic debate: protoplanetary nebula or young stellar object? We present the first 2μm image of IRAS 06562−0337, which reveals an extended diffuse nebula containing approximately 70 stars inside a 30 radius around a bright, possibly resolved, central object. The derived stellar luminosity function is consistent with that expected from a single c...

We study the nature of the extended near-UV emission in the inner kiloparsec of a sample of 15 Seyfert galaxies which have both near-UV (F330W) and narrow band [OIII] high resolution Hubble images. For the majority of the objects we find a very similar morphology in both bands. From the [OIII] images we construct synthetic images of the nebular continuum plus the emission line contribution expe...