English
Related papers

Related papers: Spherical Harmonics for the 1D Radiative Transfer …

200 papers

Adaptive optics systems are critical in any application where highly resolved imaging or beam control must be performed through a dynamic medium. Such applications include astronomy and free-space optical communications, where light…

Secondary eclipses and phase curves reveal information about the reflectivity and heat distribution in exoplanet atmospheres. The phase curve is composed of a combination of reflected, and thermally emitted light from the planet, and for…

Instrumentation and Methods for Astrophysics · Physics 2017-09-27 Ben Placek , Daniel Angerhausen , Kevin H. Knuth

A novel method for solving the linear radiative transport equation (RTE) in a three-dimensional homogeneous medium is proposed and illustrated with numerical examples. The method can be used with an arbitrary phase function A(s,s') with the…

Mathematical Physics · Physics 2007-05-23 George Panasyuk , John C. Schotland , Vadim A. Markel

This report describes the experimental results obtained using a proposed variational Retinex algorithm for controlled illumination correction. Two colour restoration and enhancement schemes of the algorithm are presented for drastically…

Computer Vision and Pattern Recognition · Computer Science 2017-02-07 U. A. Nnolim

Coherent diffractive imaging is unique as the only route for achieving diffraction-limited spatial resolution in the extreme ultraviolet and X-ray regions, limited only by the wavelength of the light. Recently, advances in coherent short…

I present an exact and explicit solution to the scalar (Stokes flux intensity) radio interferometer imaging equation on a spherical surface which is valid also for non-coplanar interferometer configurations. This imaging equation is…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 T. D. Carozzi

We present a calibrated database of reflectance spectra for the solar system planets (i.e., Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune) and for Titan, spanning from the ultraviolet to the near infrared. We considered data…

Earth and Planetary Astrophysics · Physics 2025-12-23 Allison Payne , Geronimo L. Villanueva , Vincent Kofman , Thomas J. Fauchez , Sara Faggi , Avi M. Mandell , Aki Roberge , Eleonora Alei

We present two new accurate and efficient method to compute the formal solution of the polarized radiative transfer equation. In this work, the source function and the absorption matrix are approximated using quadratic and cubic Bezier…

Solar and Stellar Astrophysics · Physics 2015-06-12 J. de la Cruz Rodríguez , N. Piskunov

Eliminating reflections caused by incident light interacting with reflective medium remains an ill-posed problem in the image restoration area. The primary challenge arises from the overlapping of reflection and transmission components in…

Computer Vision and Pattern Recognition · Computer Science 2025-09-17 Pengbo Guo , Chengxu Liu , Guoshuai Zhao , Xingsong Hou , Jialie Shen , Xueming Qian

Radiative transfer is a fundamental process in astrophysics, essential for both interpreting observations and modeling thermal and dynamical feedback in simulations via ionizing radiation and photon pressure. However, numerically solving…

Instrumentation and Methods for Astrophysics · Physics 2025-11-12 Rune Rost , Lorenzo Branca , Tobias Buck

Context. Direct imaging of exoplanets takes advantage of state-of-the-art adaptive optics (AO) systems, coronagraphy, and post-processing techniques. Coronagraphs attenuate starlight to mitigate the unfavorable flux ratio between an…

Instrumentation and Methods for Astrophysics · Physics 2022-09-21 Axel Potier , Johan Mazoyer , Zahed Wahhaj , Pierre Baudoz , Gael Chauvin , Raphael Galicher , Garreth Ruane

Modern Giant Segmented Mirror Telescopes (GSMTs) like the Extremely Large Telescope, which is currently under construction, depend heavily on Adaptive Optics (AO) systems to correct for atmospheric distortions. However, a residual blur…

Instrumentation and Methods for Astrophysics · Physics 2023-07-05 Roland Wagner , Jenny Niebsch , Ronny Ramlau

Transient imaging or light-in-flight techniques capture the propagation of an ultra-short pulse of light through a scene, which in effect captures the optical impulse response of the scene. Recently, it has been shown that we can capture…

Computer Vision and Pattern Recognition · Computer Science 2015-12-22 Ryuichi Tadano , Adithya Kumar Pediredla , Kaushik Mitra , Ashok Veeraraghavan

Time-resolved photometry is an important new probe of the physics of condensate clouds in extrasolar planets and brown dwarfs. Extreme adaptive optics systems can directly image planets, but precise brightness measurements are challenging.…

We consider the radiation transfer problem in the discrete-ordinate, plane-parallel approach. We introduce two benchmark problems with exact known solutions and show that for strongly non-homogeneous media the homogeneous layers…

Computational Physics · Physics 2007-05-23 M. -P. Zorzano , A. M. Mancho , L. Vazquez

Historically, spectroscopic techniques have been essential for studying the optical properties of thin solid films. However, existing formulae for both normal transmission and reflection spectroscopy often rely on simplified theoretical…

Coupling to longitudinal modes of thin spherical shells, under Gaussian-beam illumination, was explored with a theoretical method based on Fourier-optics analysis and vector spherical harmonics. The illumination frequency band was fixed…

A fast algorithm is developed for the directional correlation of scalar band-limited signals and band-limited steerable filters on the sphere. The asymptotic complexity associated to it through simple quadrature is of order O(L^5), where 2L…

Astrophysics · Physics 2011-02-11 Y. Wiaux , L. Jacques , P. Vielva , P. Vandergheynst

In this paper we present an expansion of the technique of characterizing nonlinear optics from off-energy orbits (NOECO) to cover harmonic sextupoles in storage rings. The existing NOECO technique has been successfully used to correct the…

Accelerator Physics · Physics 2023-03-08 Yongjun Li , Derong Xu , Victor Smaluk , Robert Rainer

We present the implementation of a radiative transfer solver with coherent scattering in the new BIFROST code for radiative magneto-hydrodynamical (MHD) simulations of stellar surface convection. The code is fully parallelized using MPI…

Solar and Stellar Astrophysics · Physics 2017-11-08 W. Hayek , M. Asplund , M. Carlsson , R. Trampedach , R. Collet , B. V. Gudiksen , V. H. Hansteen , J. Leenaarts