Related papers: Comparison of cloud models for Brown Dwarfs
We have calculated the radiation field, dust grain temperatures, and far infrared emissivity of numerical models of turbulent molecular clouds. When compared to a uniform cloud of the same mean optical depth, most of the volume inside the…
As a tool to interpret nearby and high redshift galaxy data from optical to K-band we present our chemically consistent spectrophotometric evolutionary synthesis models. These models take into account the increasing initial metallicity of…
We present self-consistent dynamical models for dust driven winds of carbon-rich AGB stars. The models are based on the coupled system of frequency-dependent radiation hydrodynamics and time-dependent dust formation. We investigate in…
We are studying the effects of submm observations on the total dust mass and thus dust-to-gas mass ratio measurements. We gather a wide sample of galaxies that have been observed at submm wavelengths to model their Spectral Energy…
A variety of observations provide evidence for vigorous motion in the atmospheres of brown dwarfs and directly imaged giant planets. Motivated by these observations, we examine the dynamical regime of the circulation in the atmospheres and…
Y dwarfs are the coolest spectral class of brown dwarf. They have effective temperatures less than 500 K, with the coolest detection as low as ~250 K. Their spectra are shaped predominantly by gaseous water, methane, and ammonia. At the…
We present an analysis of brown dwarf model spectra in the mid-infrared spectral region (5 - 20 microns), in anticipation of data obtained with the Space Infrared Telescope Facility. The mid-infrared spectra of brown dwarfs are in several…
Ground-based and spacecraft telescopic observations, combined with an intensive modeling effort, have greatly enhanced our understanding of hot giant planets and brown dwarfs over the past ten years. Although these objects are all fluid,…
In cosmology, the quest for primordial $B$-modes in cosmic microwave background (CMB) observations has highlighted the critical need for a refined model of the Galactic dust foreground. We investigate diffusion-based modeling of the dust…
The growing field of exoplanetary atmospheric modelling has seen little work on standardised benchmark tests for its models, limiting understanding of the dependence of results on specific models and conditions. With spatially resolved…
Observations across the electromagnetic spectrum of radiative processes involving interstellar dust -- emission, extinction, and scattering -- are used to constrain the parameters of dust models and more directly to aid in foreground…
We examine the dust-to-gas ratio as a function of metallicity for dwarf galaxies [dwarf irregular galaxies (dIrrs) and blue compact dwarf galaxies (BCDGs)]. Using a one-zone model and adopting the instantaneous recycling approximation, we…
Models of thermal emission of neutron stars, presumably formed in their atmospheres, are needed to infer the surface temperatures, magnetic fields, chemical composition, and neutron star masses and radii from the observational data. This…
Dwarf galaxies pose significant challenges for cosmological models. In particular, current models predict a dark matter density that is divergent at the center, in sharp contrast with observations which indicate an approximately constant…
We report direct observational evidence for a latitudinal dependence of dust cloud opacity in ultracool dwarfs, indicating that equatorial latitudes are cloudier than polar latitudes. These results are based on a strong positive correlation…
We examine several different simplified approaches for modelling the chemistry of CO in three-dimensional numerical simulations of turbulent molecular clouds. We compare the different models both by looking at the behaviour of integrated…
The review contains an analysis of the observed and model curves of the interstellar extinction and polarization. The observations mainly give information on dust in diffuse and translucent interstellar clouds. The features of various dust…
We present evolutionary calculations for very-low-mass stars and brown dwarfs based on synthetic spectra and non-grey atmosphere models which include dust formation and opacity, i.e. objects with $\te\simle 2800$ K. The interior of the most…
The gas-to-dust mass ratios found for interstellar dust within the Solar System, versus values determined astronomically for the cloud around the Solar System, suggest that large and small interstellar grains have separate histories, and…
Planets have been detected around a variety of stars, including low-mass objects, such as brown dwarfs. However, such extreme cases are challenging for planet formation models. Recent sub-millimeter observations of disks around brown dwarf…