Continuum-scale equations of radiative transfer and corresponding boundary conditions are derived for a general case of a multi-component medium consisting of arbitrary-type, non-isothermal and non-uniform components in the limit of geometrical optics. The link between the discrete and continuum scales is established by volume averaging of the discrete-scale equations of radiative transfer by a...

Radiative transfer describes the transport of electromagnetic energy in macroscopic environments when polarization effects are neglected [38]. The theory originates in work by Bouguer [6, 7] and Lambert [23] in the 18th century where the intensity of light and its measurement were first studied systematically, cf. Fig. 1, and in the 19th and early 20th century the theory was extended to include...

The internal dust extinction in spiral galaxies can affect our understanding of their structure and morphology, as well as our perception of the distant universe in the background. The intrinsic properties of the stellar and dust components can be studied by comparing the observed appearance of a dusty spiral in the optical with a radiative transfer model. The absorbed starlight is re-radiated ...

Technical note: The libRadtran software package for radiative transfer calculations – description and examples of use B. Mayer and A. Kylling Deutsches Zentrum für Luftund Raumfahrt (DLR), Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany St. Olavs Hospital, Trondheim University Hospital, Norway previously at: Norwegian Institute for Air Research (NILU), Kjeller, Norway Received: 25...

We present a new 3D continuum radiative transfer code, MCFOST, based on a Monte-Carlo method. The reliability and efficiency of the code is tested by comparison with five different radiative transfer codes previously tested by Pascucci et al. (2004), using a 2D disk configuration. When tested against the same disk configuration, no significant difference is found between the temperature and SED...

An ideal blackbody resides inside a cavity in a medium of temperature T that is also an ideal blackbody. If the small black body is initially at temperature T could its temperature evolve to an equilibrium temperature T ′ different from T if the inner surface of the cavity is covered with a passive filter? For example, the filter might be an ideal transmitter for light of wavelength λ < λf (or ...

Aims. An efficient algorithm for calculating radiative transfer on massively parallel computers using domain decomposition is presented. Methods. The integral formulation of the transfer equation is used to divide the problem into a local but compute-intensive part for calculating the intensity and optical depth integrals, and a nonlocal part for communicating the intensity between adjacent pro...

Understanding how light interacts with sea water is a fascinating problem in itself, as well as being fundamental to Relds as diverse as biological primary production, mixed-layer thermodynamics, photochemistry, lidar bathymetry, ocean-color remote sensing, and visual searching for submerged objects. For these reasons, optics is one of the fastest growing oceanographic research areas. Radiative...

We develop a method of analyzing radio frequency spectral line observations to derive data on the temperature, density, velocity, and molecular abundance of the emitting gas. The method incorporates a radiative transfer code with a new technique for handling overlapping hyperfine emission lines within the accelerated lambda iteration algorithm and a heuristic search algorithm based on simulated...