141 research outputs found
A linear model of atmospheric circulation
Linear model of atmospheric circulation used for atmosphere of Venu
Computation of three-dimensional supersonic flows with shock waves
Computation of three dimensional supersonic flows with shock wave
A direct method for calculation of the flow about an axisymmetric blunt body at angle of attack
Direct calculation method for supersonic inviscid flow around axisymmetric blunt body with conically reentrant afterbody flying at large angle of attac
Supersonic flow over convex and concave shapes with radiation and ablation effects
Numerical method of unsteady adjustment for calculating inviscid flow fields about convex and concave shapes on atmospheric entry with ablatio
A method for determining catalytic efficiency of surfaces
Catalytic efficiency calculations for surface heat flux and heat transfer during atmospheric reentr
General circulation in the atmosphere of Venus driven by polar and diurnal variations of surface temperature
Mathematical model for Venus atmosphere circulation pattern determined by polar and diurnal temperature variation
The circumstellar disk of HH 30. Searching for signs of disk evolution with multi-wavelength modeling
Circumstellar disks are characteristic for star formation and vanish during
the first few Myr of stellar evolution. During this time planets are believed
to form in the dense midplane by growth, sedimentation and aggregation of dust.
Indicators of disk evolution, such as holes and gaps, can be traced in the
spectral energy distribution (SED) and spatially resolved images.
We aim to construct a self-consistent model of HH 30 by fitting all available
continuum observations simultaneously. New data sets not available in previous
studies, such as high-resolution interferometric imaging with the Plateau de
Bure Interferometer (PdBI) at lambda = 1.3 mm and SED measured with IRS on the
Spitzer Space Telescope in the mid-infrared, put strong constraints on
predictions and are likely to provide new insights into the evolutionary state
of this object.
A parameter study based on simulated annealing was performed to find unbiased
best-fit models for independent observations made in the wavelength domain
lambda ~ 1 micron ... 4 mm. The method essentially creates a Markov chain
through parameter space by comparing predictions generated by our
self-consistent continuum radiation transfer code MC3D with observations.
We present models of the edge-on circumstellar disk of HH 30 based on
observations from the near-infrared to mm-wavelengths that suggest the presence
of an inner depletion zone with about 45 AU radius and a steep decline of mm
opacity beyond 140 AU. Our modeling indicates that several modes of dust
evolution such as growth, settling, and radial migration are taking place in
this object.
High-resolution observations of HH 30 at different wavelengths with
next-generation observatories such as ALMA and JWST will enable the modeling of
inhomogeneous dust properties and significantly expand our understanding of
circumstellar disk evolution.Comment: Accepted for publication in Astronomy and Astrophysic
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