We consider the atmospheric flow on short-period extra-solar planets through two-dimensional numerical simulations of hydrodynamics with radiation transfer. The observed low eccentricity of these planets indicates that tidal dissipation within them has been effective in circularizing their orbits and synchronizing their spins. Consequently, one side of these planets (the day side) is always exp...

Stellar mass compact objects in short period (P . 10 s) orbits about a 10–10M⊙ massive black hole (MBH) are thought to be a significant continuous-wave source of gravitational radiation for the ESA/NASA Laser Interferometer Space Antenna (LISA) gravitational wave detector. These extreme mass-ratio inspiral sources began in long-period, nearly parabolic orbits that have multiple close encounters...

Forming stars emit a substantial amount of radiation into their natal environment. We use ORION, an adaptive mesh refinement (AMR) three-dimensional gravito-radiation-hydrodyanics code, to simulate low-mass star formation in a turbulent molecular cloud. We compare the distribution of stellar masses, accretion rates, and temperatures in the cases with and without radiative transfer, and we demon...

Stellar mass compact objects in short period (P . 10 s) orbits about a 10–10M⊙ massive black hole (MBH) are thought to be a significant continuous-wave source of gravitational radiation for the ESA/NASA Laser Interferometer Space Antenna (LISA) gravitational wave detector. These extreme mass-ratio inspiral sources began in long-period, nearly parabolic orbits that have multiple close encounters...

We study the far infrared (60–500 μm) colours of late-type galaxies in the Herschel Reference Survey, a K-band selected, volume limited sample of nearby galaxies. The far infrared colours are correlated with each other, with tighter correlations for the indices that are closer in wavelength. We also compare the different colour indices to various tracers of the physical properties of the target...

The feedback effects of massive stars on their galactic and intergalactic environments can dominate evolutionary processes in galaxies and affect cosmic structure in the Universe. Only the Local Group offers the spatial resolution to quantitatively study feedback processes on a variety of scales. Lyman continuum radiation from hot, luminous stars ionizes H ii regions and is believed to dominate...

We model how the mid-IR colors of young stellar objects (YSOs) vary with stellar temperature. The spectral energy distribution (SED) of each object has contributions from the thermal emission of circumstellar dust, from direct stellar photospheric emission, and from scattered stellar emission. We first isolate the effects of stellar contributions (direct + scattered) to the SED using homologous...

The new generation of gravitational wave (GW) detectors have the potential to open a novel window onto the violent dynamics of core collapse. Although it is certain that core collapse events generate gravitational radiation, understanding the characteristics of the radiation — whether it can be measured with these detectors, and the best way to go about doing so — is a challenging problem. In t...

Cosmic ray protons accelerated in the internal shocks of a long duration gamma ray burst can escape the fireball by converting to neutrons. Hadronic interactions of these neutrons inside a stellar wind bubble created by the progenitor star will produce TeV gamma rays via neutral meson decay and synchrotron radiation by charged pion-decay electrons in the wind magnetic field. Such gamma rays may...

Context. Spectral synthesis calculations based on three-dimensional stellar atmosphere models are limited by the affordable angular resolution of the radiation field. This hampers an accurate treatment of rotational line broadening. Aims. We aim to find a treatment of rotational broadening of a spherical star when the radiation field is only available at a modest number of limb-angles. Methods....