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Related papers: The hybrid opacity code SCO-RCG: recent developmen…

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Modelling the interaction between ionizing photons emitted from massive stars and their environment is essential to further our understanding of galactic ecosystems. We present a hybrid Radiation-Hydrodynamics (RHD) scheme that couples an…

Instrumentation and Methods for Astrophysics · Physics 2024-04-29 Cheryl S. C. Lau , Maya A. Petkova , Ian A. Bonnell

This paper presents a novel scheme dubbed Collision Diversity (CoD) SCRAM, which is provisioned to meet the challenging requirements of the future 6G, portrayed in massive connectivity, reliability, and ultra-low latency. The conventional…

Information Theory · Computer Science 2024-10-11 Sally Nafie , Joerg Robert , Albert Heuberger

Solving the continuum radiative transfer equation in high opacity media requires sophisticated numerical tools. In order to test the reliability of such tools, we present a benchmark of radiative transfer codes in a 2D disc configuration.…

Solar and Stellar Astrophysics · Physics 2015-05-13 C. Pinte , T. J. Harries , M. Min , A. M. Watson , C. P. Dullemond , P. Woitke , F. Menard , M. C. Duran-Rojas

Hybrid codes are widely used to model ion-scale phenomena in space plasmas. Hybrid codes differ from full particle (PIC) codes in that the electrons are modeled as a fluid that is usually assumed to be massless, while the electric field is…

Plasma Physics · Physics 2022-04-05 D. Winske , Homa Karimabadi , Ari Le , N. Omidi , Vadim Roytershteyn , Adam Stanier

Absorption-line spectroscopy is a powerful tool used to estimate element abundances in the nearby as well as distant universe. The accuracy of the abundances thus derived is, naturally, limited by the accuracy of the atomic data assumed for…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Romas Kisielius , Varsha P. Kulkarni , Gary J. Ferland , Pavel Bogdanovich , Matt L. Lykins

The interpretation of the intensity and polarization of the spectral line radiation produced in the atmosphere of the Sun and of other stars requires solving a radiative transfer problem that can be very complex, especially when the main…

Solar and Stellar Astrophysics · Physics 2015-06-16 Jiri Stepan , Javier Trujillo Bueno

High precision atomic data is indispensable for experiments involving studies of fundamental interactions, astrophysics, atomic clocks, plasma science, and others. We develop new parallel atomic structure codes and explore the difficulties…

Atomic Physics · Physics 2021-03-11 C. Cheung , M. S. Safronova , S. G. Porsev

An iterative algorithm is presented for soft-input-soft-output (SISO) decoding of Reed-Solomon (RS) codes. The proposed iterative algorithm uses the sum product algorithm (SPA) in conjunction with a binary parity check matrix of the RS…

Information Theory · Computer Science 2009-09-29 Jing Jiang , Krishna R. Narayanan

A theoretical model based on the method of super transition arrays (STA) is used to compute the emissivities, opacities and average ionization states of carbon (C) and polystyrene (CH) plasmas in the warm-dense matter regime in which the…

Plasma Physics · Physics 2018-11-20 Teck-Ghee Lee , M. Busquet , M. Klapisch , J. W. Bates , A. J. Schmitt , S. X. Hu , J. Giuliani

In the Super-Transition-Array statistical method for the computation of radiative opacity of hot dense matter, the moments of the absorption or emission features involve partition functions with reduced degeneracies, occurring through the…

Atomic Physics · Physics 2024-05-14 Jean-Christophe Pain , Brian Wilson

An extended version of the R-matrix methodology is presented for calculation of radiative parameters for improved plasma opacities. Contrast and comparisons with existing methods primarily relying on the Distorted Wave (DW) approximation…

Solar and Stellar Astrophysics · Physics 2023-08-30 A. K. Pradhan , S. N. Nahar , W. Eissner

Realization of spin crossover (SCO) based applications requires studying of spin state switching characteristics of SCO complex molecules at nanostructured environments especially on-surface. Except for a very few cases, the SCO of a…

Absorption lines of H$_2$ and HD molecules observed at high redshift in the line of sight towards quasars are a test ground to search for variation of the proton-to-electron mass ratio $\mu$. For this purpose, results from astronomical…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-13 W. Ubachs , E. J. Salumbides , M. T. Murphy , H. Abgrall , E. Roueff

A new formalism and computer code, ASTRA (AttoSecond TRAnsitions), has been developed to treat the interactions of short, intense radiation with molecules. The formalism makes extensive use of transition density matrices, computed using a…

Line intensity mapping (LIM) is an emerging technique with a unique potential to probe a wide range of scales and redshifts. Realizing the full potential of LIM, however, relies on accurate modeling of the signal. We introduce an extended…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-23 Azadeh Moradinezhad Dizgah , Farnik Nikakhtar , Garrett K. Keating , Emanuele Castorina

We describe \ASTRA{} (AttoSecond TRAnsitions), a new close-coupling approach to molecular ionization that uses many-body transition density matrices between ionic states with arbitrary spin and symmetry, in combination with hybrid integrals…

Using integral transforms to the end of lines detection in images with complex background, makes the detection a hard task needing additional processing to manage the detection. As an integral transform, the Scale Space Radon Transform…

Computer Vision and Pattern Recognition · Computer Science 2023-11-16 Aicha Baya Goumeidane , Djemel Ziou , Nafaa Nacereddine

Parameterizing radiative transfer in means navigating trade-offs between physical accuracy and conceptual clarity. However, currently available schemes sit at the extremes of this spectrum: correlated-k schemes are fast and accurate but…

Atmospheric and Oceanic Physics · Physics 2025-08-14 Andrew I. L. Williams

SpK is part of the numerical codebase at Imperial College London used to model high energy density physics (HEDP) experiments. SpK is an efficient atomic and microphysics code used to perform detailed configuration accounting calculations…

The computation of radiative opacity or emissivity of hot dense matter is a challenging task. It requires accounting for an immense number of energy levels and lines across various excitation and ionization states. Whether in local…

Atomic Physics · Physics 2025-09-03 Jean-Christophe Pain , Djamel Benredjem