English
Related papers

Related papers: Longwave radiative analysis of cloudy scattering a…

200 papers

We consider the Hartree-Fock equation in 1D, for a small and localised initial data and a finite measure potential. We show that there is no long range scattering due to a nonlinear cancellation between the direct term and the exchange term…

Analysis of PDEs · Mathematics 2025-03-11 Cyril Malézé

In a recent article the authors showed that the radiative Transfer equations with multiple frequencies and scattering can be formulated as a nonlinear integral system. In the present article, the formulation is extended to handle reflective…

Numerical Analysis · Mathematics 2023-06-12 Olivier Pironneau , Pierre-Henri Tournier

The Earth's atmosphere affects ground-based astronomical observations. Scattering, absorption, and radiation processes deteriorate the signal-to-noise ratio of the data received. For scheduling astronomical observations it is, therefore,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 S. Noll , W. Kausch , M. Barden , A. M. Jones , C. Szyszka , S. Kimeswenger , J. Vinther

In this article we propose a numerical algorithm to compute the intensity and polarization of a polychromatic electromagnetic radiation crossing a medium with graded refractive index and modeled by the Vector Radiative Refractive Transfer…

Analysis of PDEs · Mathematics 2024-08-06 Olivier Pironneau

High energy electron and muon neutrino propagation through the Earth has been performed using the Monte Carlo technique. We focused our attention on the effect of neutral current deep inelastic interactions compared to that of charged…

High Energy Physics - Phenomenology · Physics 2014-11-17 Annalisa Labbate , Teresa Montaruli , Igor Sokalski

Cosmic rays interact with nuclei in the Earth's atmosphere to produce extensive air showers, which give rise to the atmospheric muon flux. Temperature fluctuations in the atmosphere influence the rate of muons measured in deep underground…

High Energy Physics - Phenomenology · Physics 2025-09-23 Amanda Alves , Lilly Pyras , Dennis Soldin , Stef Verpoest

We compare four different methods to calculate radiative transfer through a magnetized stellar atmosphere, and apply them to the case of magnetic white dwarfs. All methods are numerically stable enough to allow determination of the magnetic…

Astrophysics · Physics 2007-05-23 Stefan Jordan , Holger Schmidt

The alignment of nuclear states resonantly formed in nuclear excitation by electron capture (NEEC) is studied by means of a density matrix technique. The vibrational excitations of the nucleus are described by a collective model and the…

Atomic Physics · Physics 2008-11-26 Adriana Pálffy , Zoltán Harman , Andrey Surzhykov , Ulrich D. Jentschura

This review presents basic equations for the solution of the NLTE radiative transfer problem for trace elements and methods for its solution are summarized. The importance of frequency coupling in radiative transfer in stellar atmospheres…

Solar and Stellar Astrophysics · Physics 2015-05-19 Jiri Kubat

Spectral analysis by means of NLTE model atmospheres has presently arrived at a high level of sophistication. High-resolution spectra of central stars of planetary nebulae can be reproduced in detail from the infrared to the X-ray…

Astrophysics · Physics 2007-09-04 Thomas Rauch , Klaus Werner , Marc Ziegler , Jeffrey W. Kruk , Cristina M. Oliveira

Many stars, active galactic nuclei, accretion discs etc. are affected by the stochastic variations of temperature, turbulent gas motions, magnetic fields, number densities of atoms and dust grains. These stochastic variations influence on…

Solar and Stellar Astrophysics · Physics 2017-12-20 N. A. Silant'ev , G. A. Alekseeva , V. V. Novikov

We present a numerical method and computer code to calculate the radiative transfer and excitation of molecular lines. Formulating the Monte Carlo method from the viewpoint of cells rather than photons allows us to separate local and…

Astrophysics · Physics 2007-05-23 Michiel R. Hogerheijde , Floris F. S. van der Tak

Light transfer in gradient-index media generally follows curved ray trajectories, which will cause light beam to converge or diverge during transfer and induce the rotation of polarization ellipse even when the medium is transparent.…

Optics · Physics 2014-12-16 J. M. Zhao , J. Y. Tan , L. H. Liu

We simulate convection near the solar surface, where the continuum optical depth is of order unity. Hence, to determine the radiative heating and cooling in the energy conservation equation, we must solve the radiative transfer equation…

Astrophysics · Physics 2007-05-23 Robert Stein , Aake Nordlund

The sensitivity of the radiative flux at the top of the atmosphere to surface temperature perturbations cannot be directly observed. The relationship between sea surface temperature (SST) and top-of-atmosphere radiation can be estimated…

Atmospheric and Oceanic Physics · Physics 2025-07-22 Senne Van Loon , Maria Rugenstein , Elizabeth A. Barnes

We explore cloudy, extended H2-He atmosphere scenarios for the warm super-Earth GJ 1214b using an optimal estimation retrieval technique. This planet, orbiting an M4.5 star only 13 pc from the Earth, is of particular interest because it…

Earth and Planetary Astrophysics · Physics 2014-03-27 Joanna K. Barstow , Suzanne Aigrain , Patrick G. J. Irwin , Leigh N. Fletcher , Jae-Min Lee

Model atmospheres of isolated neutron stars with low magnetic field are calculated with Compton scattering taking into account. Models with effective temperatures 1, 3 and 5 MK, with two values of surface gravity log(g)g = 13.9 and 14.3),…

Astrophysics · Physics 2008-11-26 V. Suleimanov , K. Werner

Alfven waves propagating in a vertically stratified plasma, such as those travelling from the solar photosphere to the corona, are partially reflected due to the gradient in the Alfven speed. Wave reflection naturally results in the…

Solar and Stellar Astrophysics · Physics 2025-04-15 Roberto Soler

The atmospheres of small, potentially rocky exoplanets are expected to cover a diverse range in composition and mass. Studying such objects therefore requires flexible and wide-ranging modeling capabilities. We present in this work the…

Earth and Planetary Astrophysics · Physics 2020-07-29 M. Scheucher , F. Wunderlich , J. L. Grenfell , M. Godolt , F. Schreier , D. Kappel , R. Haus , K. Herbst , H. Rauer

Air pollution is a significant global health risk, contributing to millions of premature deaths annually. Nitrogen dioxide (NO2), a harmful pollutant, disproportionately affects urban areas where monitoring networks are often sparse. We…

Signal Processing · Electrical Eng. & Systems 2025-05-12 Finn Gueterbock , Raul Santos-Rodriguez , Jeffrey N. Clark