English
Related papers

Related papers: Ray-tracing for complex astrophysical high-opacity…

200 papers

Ultrasound Tomography has seen a revival of interest in the past decade, especially for breast imaging, due to improvements in both ultrasound and computing hardware. In particular, three-dimensional ultrasound tomography, a fully…

Computational Physics · Physics 2020-05-27 Ashkan Javaherian , Felix Lucka , Ben Cox

We demonstrate a motion-free intensity diffraction tomography technique that enables direct inversion of 3D phase and absorption from intensity-only measurements for weakly scattering samples. We derive a novel linear forward model,…

Image and Video Processing · Electrical Eng. & Systems 2018-06-26 Ruilong Ling , Waleed Tahir , Hsing-Ying Lin , Hakho Lee , Lei Tian

Aims. We present an implementation of an algorithm for 3D time-dependent Monte Carlo radiative transfer. It allows one to simulate temperature distributions as well as images and spectral energy distributions of the scattered light and…

Instrumentation and Methods for Astrophysics · Physics 2022-12-14 A. Bensberg , S. Wolf

The integro-differential formulation of the RTE and its solution by iterations on the source has been extended here to handle anisotropic scattering. The iterative part of the method is O(N ln N ), thanks to an efficient use of H-matrices.…

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

We present a new approach to numerically model continuum radiative transfer based on the Optically Thin Variable Eddington Tensor (OTVET) approximation. Our method insures the exact conservation of the photon number and flux (in the…

Astrophysics · Physics 2009-11-06 Nickolay Y. Gnedin , Tom Abel

Discrete flow mapping was recently introduced as an efficient ray based method determining wave energy distributions in complex built up structures. Wave energy densities are transported along ray trajectories through polygonal mesh…

Computational Physics · Physics 2016-12-21 Janis Bajars , David Chappell , Niels Sondergaard , Gregor Tanner

The radiative transfer problem is considered in dense gas-dust clouds. Physical parameters are adopted in simulations corresponding to gas-dust clouds in the circumstellar envelopes of late-type stars. An one-dimensional plane-parallel slab…

Astrophysics of Galaxies · Physics 2015-06-17 Aleksandr Nesterenok

Radiative transfer is a notoriously difficult and computationally demanding problem. Yet, it is an indispensable ingredient in nearly all astrophysical and cosmological simulations. Choosing an appropriate discretization scheme is a crucial…

Instrumentation and Methods for Astrophysics · Physics 2020-12-01 Frederik De Ceuster , Jan Bolte , Ward Homan , Silke Maes , Jolien Malfait , Leen Decin , Jeremy Yates , Peter Boyle , James Hetherington

To capture the 3D information of a scene, conventional techniques often require multiple 2D images of the scene to be captured from different perspectives. In this work we demonstrate the reconstruction of a scene's 3D information through…

Quantum Physics · Physics 2022-01-05 Yingwen Zhang , Antony Orth , Duncan England , Benjamin Sussman

A finite element method for solving the resonance line transfer problem in moving media is presented. The algorithm works in three spatial dimensions on unstructured grids which are adaptively refined by means of an a posteriori error…

Astrophysics · Physics 2009-11-07 E. Meinkoehn , S. Richling

Prediction of particle radiative heat transfer flux is an important task in the large discrete granular systems, such as pebble bed in power plants and industrial fluidized beds. For particle motion and packing, discrete element method…

Soft Condensed Matter · Physics 2020-06-24 Hao Wu , Shuang Hao

A new two-dimensional axi-symmetric ultraviolet radiative transfer code is presented, which is used to calculate photodissociation and ionization rates for use in chemistry models of flaring circumstellar disks. Scattering and absorption of…

We introduce two new methods that are designed to improve the realism and utility of large, active region-scale 3D MHD models of the solar atmosphere. We apply these methods to RADMHD, a code capable of modeling the Sun's upper convection…

Solar and Stellar Astrophysics · Physics 2010-05-06 William P. Abbett , George H. Fisher

Modeling radio frequency (RF) signal propagation is essential for understanding the environment, as RF signals offer valuable insights beyond the capabilities of RGB cameras, which are limited by the visible-light spectrum, lens coverage,…

Machine Learning · Computer Science 2025-10-07 Kyoungjun Park , Yifan Yang , Changhan Ge , Lili Qiu , Shiqi Jiang

We consider the problem of radiative transfer in stellar atmospheres where the index of refraction departs from unity and is a function of density and temperature. We present modified Feautrier and Lambda-iteration methods to solve the…

Astrophysics · Physics 2009-11-10 P. M. Kowalski , D. Saumon

Context. Magnetic fields are important to the dynamics of many astrophysical processes and can typically be studied through polarization observations. Polarimetric interferometry capabilities of modern (sub)millimeter telescope facilities…

Instrumentation and Methods for Astrophysics · Physics 2020-04-08 Boy Lankhaar , Wouter Vlemmings

Radio propagation modeling is essential in telecommunication research, as radio channels result from complex interactions with environmental objects. Recently, Machine Learning has been attracting attention as a potential alternative to…

High redshift sources suffer from magnification or demagnification due to weak gravitational lensing by large scale structure. One consequence of this is that the distance-redshift relation, in wide use for cosmological tests, suffers…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Madhura Killedar , Paul D. Lasky , Geraint F. Lewis , Chris J. Fluke

The Galactic Cold Cores (GCC) project has made Herschel observations of interstellar clouds where Planck detected compact sources of cold dust emission. Our aim is to characterise the structure of the clumps and their parent clouds. We also…

Astrophysics of Galaxies · Physics 2018-06-20 M. Juvela , J. Malinen , J. Montillaud , V. -M. Pelkonen , I. Ristorcelli , L. V. Toth

The brightness of the emission from coronal loops in the solar atmosphere is strongly dependent on the temperature and density of the confined plasma. After a release of energy, these loops undergo a heating and upflow phase, followed by a…

Solar and Stellar Astrophysics · Physics 2019-03-20 C. D. Johnston , S. J. Bradshaw
‹ Prev 1 4 5 6 7 8 10 Next ›