相关论文: Codes for optically thick and hot photoionized med…

Spectral lines of helium are commonly observed on the Sun. These observations contain important informations about physical conditions and He/H abundance variations within solar outer structures. The modeling of chromospheric and coronal…

Accurate radiative transfer coefficients (emissivities, absorptivities, and rotativities) are needed for modeling radiation from relativistically hot, magnetized plasmas such as those found in Event Horizon Telescope sources. Here we…

We present an extension to the short-characteristic ray-tracing and non-equilibrium photon-ionization code C2Ray. The new version includes the effects of helium and improved multi-frequency heating. The motivation for this work is to be…

A revised and greatly improved version of the 3D continuum radiative transfer code MC3D is presented. It is based on the Monte-Carlo method and solves the radiative transfer problem self-consistently. It is designed for the simulation of…

In this paper, we present a new approach for the exact calculation of band structure in one-dimensional periodic media, such as photonic crystals and superlattices, based on the recently reported differential transfer matrix method (DTMM).…

We develop a new numerical scheme for solving the radiative transfer equation in a spherically symmetric system. This scheme does not rely on any kind of diffusion approximation and it is accurate for optically thin, thick, and intermediate…

We study the standard spectral line radiative transfer equation for media consisting of resonant atoms and non-resonant components (the dust grains and the atoms without considered spectral transition). Our goal is to study the intensity…

In a previous article, with a new code designed for a photoionized thick hot medium using a full transfer treatment of both lines and continuum, we have studied the He-like emission of a medium photoionized by an X-ray source. We considered…

X-ray transition radiation can be used to measure the Lorentz factor of relativistic particles. Standard transition radiation detectors (TRDs) typically incorporate thin plastic foil radiators and gas-filled x-ray detectors, and are…

We present a new detailed model of the He I collisional-recombination spectrum based on the most up-to-date atomic data. The model accounts for radiative transfer effects and the influence of a non-zero optical depth in He I lines arising…

Optical communication channels are ultimately quantum-mechanical in nature, and we must therefore look beyond classical information theory to determine their communication capacity as well as to find efficient encoding and decoding schemes…

This work presents efficient solution techniques for radiative transfer in the smoothed particle hydrodynamics discretization. Two choices that impact efficiency are how the material and radiation energy are coupled, which determines the…

Astrophysical plasmas are subject to a tight connection between magnetic fields and the diffusion of particles, which leads to an anisotropic transport of energy. Under the fluid assumption, this effect can be reduced to an…

We derive a semi-analytic solution for the structure of conduction-mediated transition layers above an X-ray illuminated accretion disk, and calculate explicitly the X-ray line radiation resulting from both resonance line scattering and…

X-ray transition radiation can be used to measure the Lorentz factor of relativistic particles. At energies approaching gamma = E/mc^2 = 10^5, transition radiation detectors (TRDs) can be optimized by using thick (sim 5 - 10 mil) foils with…

The development of fast numerical methods for multilevel radiative transfer (RT) applications often leads to important breakthroughs in astrophysics, because they allow the investigation of problems that could not be properly tackled using…

We are investigating the effective heat transfer in complex systems involving porous media and surrounding fluid layers in the context of mathematical homogenization. We differentiate between two fundamentally different cases: Case (a),…

The macroscopic quantizations of matter into macro-atoms and radiant and thermal energies into r- and k-energy packets initiated in Paper I is completed with the definition of transition probabilities governing energy flows to and from the…

We introduce a data analysis procedure for color transparency experiments which is considerably less model dependent than the transparency ratio method. The new method is based on fitting the shape of the A dependence of the nuclear cross…

Transition-edge sensors are a type of superconducting detector that offers high energy resolution based on their sharp resistance-temperature feature in the superconducting-to-normal transition. TES X-ray microcalorimeters have typically…