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Related papers: R-Matrix calculations for opacities: I. Methodolog…

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The opportunities of the application of the recently proposed approach in optical emission spectroscopy of non-equilibrium plasmas have been studied. The approach consists of several methods of the determination of {\em absolute} particle…

Plasma Physics · Physics 2007-05-23 B. P. Lavrov , A. S. Mikhailov

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

The K-alpha resonance complexes in oxygen ions O I - O VI are theoretically computed and resonance oscillator strengths and wavelengths are presented. The highly resolved photoionization cross sections, with relativistic fine structure, are…

Astrophysics · Physics 2008-11-26 Anil K. Pradhan , Guo Xin Chen , Franck Delahaye , Sultana N. Nahar , Justin Oelgoetz

In recent years, with the rapid development of electro-optic modulators, optical computing has become a potential excellent candidate for various computing tasks. New structures and devices for optical computing are emerging one after…

Optics · Physics 2023-09-20 Yufeng Zhang , Hao Yan , Kaizhi Wang

Density matrix perturbation theory [Phys. Rev. Lett. Vol. 92, 193001 (2004)] provides an efficient framework for the linear scaling computation of response properties [Phys. Rev. Lett. Vol. 92, 193002 (2004)]. In this article, we generalize…

Computational Physics · Physics 2009-11-11 Anders M. N. Niklasson , Valery Weber , Matt Challacombe

Deep learning approaches to optical flow estimation have seen rapid progress over the recent years. One common trait of many networks is that they refine an initial flow estimate either through multiple stages or across the levels of a…

Computer Vision and Pattern Recognition · Computer Science 2019-04-11 Junhwa Hur , Stefan Roth

Nowadays, several opacity codes are able to provide data for stellar structure models, but the computed opacities may show significant differences. In this work, we present state-of-the-art precise spectral opacity calculations, illustrated…

Solar and Stellar Astrophysics · Physics 2019-04-30 Jean-Christophe Pain , Franck Gilleron , Maxime Comet

Integrated photonics computing has emerged as a promising approach to overcome the limitations of electronic processors in the post-Moore era, capitalizing on the superiority of photonic systems. However, present integrated photonics…

Optics · Physics 2023-08-15 Yuepeng Wu , Hongxiang Guo , Bowen Zhang , Jifang Qiu , Zhisheng Yang , Jian Wu

We formulate the problem of a two-level system in a linearly polarized laser field in terms of a nonlinear Riccati-type differential equation and solve the equation analytically in time intervals much shorter than half the optical period.…

Quantum Physics · Physics 2007-05-23 R. Parzynski , M. Sobczak , A. Plucinska

The full-potential linearized augmented-plane wave (FP-LAPW) method is well known to enable most accurate calculations of the electronic structure and magnetic properties of crystals and surfaces. The implementation of atomic forces has…

Condensed Matter · Physics 2009-10-31 Max Petersen , Frank Wagner , Lars Hufnagel , Matthias Scheffler , Peter Blaha , Karlheinz Schwarz

We present recent evolutions of the detailed opacity code SCO-RCG which combines statistical modelings of levels and lines with fine-structure calculations. The code now includes the Partially-Resolved-Transition-Array model, which allows…

Solar and Stellar Astrophysics · Physics 2021-03-10 Jean-Christophe Pain , Franck Gilleron , Thomas Blenski

The interest in using optical transition radiation (OTR) in high energy (multiGeV) beam diagnostics has motivated theoretical and experimental investigations on the limitations brought by diffraction on the attainable resolution. This paper…

Accelerator Physics · Physics 2007-05-23 X. Artru , R. Chehab , K. Honkavaara , A. Variola

Atomic diffusion with radiative levitation is a major transport process to consider to explain abundance anomalies in Am stars. Radiative accelerations vary from one species to another, yielding different abundance anomalies at the stellar…

Solar and Stellar Astrophysics · Physics 2024-11-20 Alain Hui-Bon-Hoa

The calculable $R$-matrix theory has been formulated successfully for regular boundary conditions with vanishing radial wave functions at the coordinate origins [P. Descouvemont and D. Baye, Rept. Prog. Phys. 73, 036301 (2010)]. We…

Nuclear Theory · Physics 2021-02-24 Dong Bai , Zhongzhou Ren

A theoretical investigation of photoabsorption and photoionization of Fe^{14+} extending beyond an earlier frame transformation R-matrix implementation is performed using a fully-correlated, Breit-Pauli R-matrix formulation including both…

Atomic Physics · Physics 2015-06-04 M. F. Hasoglu , T. W. Gorczyca , M. A. Bautista , Z. Felfli , S. T. Manson

Over the past decade, reflection matrix microscopy (RMM) and advanced image reconstruction algorithms have emerged to address the fundamental imaging depth limitations of optical microscopy in thick biological tissues and complex media. In…

Optics · Physics 2024-07-03 Sungsam Kang , Seokchan Yoon , Wonshik Choi

Mixed-gas opacities are critical for radiative transfer in stellar and substellar atmospheres. Several approaches exist to obtain net k-coefficients for arbitrary mixtures, each trading accuracy against computational cost. I introduce a…

Earth and Planetary Astrophysics · Physics 2026-05-26 Elspeth K. H. Lee

A computational model study for complete frequency redistribution linear incoherent two-level atomic radiation trapping in optically dense media using the multiple scattering representation is presented. This model study discuss at length…

Physics Education · Physics 2009-11-13 A. R. Alves-Pereira , E. J. Nunes-Pereira , J. M. G. Martinho , M. N. Berberan-Santos

Probing an atomic resonance without disturbing it is an ubiquitous issue in physics. This problem is critical in high-accuracy spectroscopy or for the next generation of atomic optical clocks. Ultra-high resolution frequency metrology…

We generalize the `renormalized' perturbation theory (RPT) formalism of Crocce & Scoccimarro (2006a) to deal with multiple fluids in the Universe and here we present calculations up to the one-loop level. We apply the approach to the…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Gabor Somogyi , Robert E. Smith
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