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

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I present HPRMAT, a high-performance solver library for the linear systems arising in R-matrix coupled-channel scattering calculations in nuclear physics. Designed as a drop-in replacement for the linear algebra routines in existing…

Computational Physics · Physics 2025-12-15 Jin Lei

Coalescence of binary neutron star give rise to electromagnetic emission, kilonova, powered by radioactive decays of r-process nuclei. Observations of kilonova associated with GW170817 provided unique opportunity to study the heavy element…

Solar and Stellar Astrophysics · Physics 2019-02-13 Gediminas Gaigalas , Daiji Kato , Pavel Rynkun , Laima Radziute , Masaomi Tanaka

We present an algorithm for computing a spectral decomposition of an interval matrix as an enclosure of spectral decompositions of particular realizations of interval matrices. The algorithm relies on tight outer estimations of eigenvalues…

Numerical Analysis · Mathematics 2025-10-07 David Hartman , Milan Hladík , David Říha

A new approach for tuning the parameters of MultiScale Retinex (MSR) based color image enhancement algorithm using a popular optimization method, namely, Particle Swarm Optimization (PSO) is presented in this paper. The image enhancement…

Computer Vision and Pattern Recognition · Computer Science 2014-09-16 M. C Hanumantharaju , M. Ravishankar , D. R Rameshbabu , V. N Manjunath Aradhya

The broadening of lines by Stark effect is an important tool for inferring electron density and temperature in plasmas. Stark-effect calculations often rely on atomic data (transition rates, energy levels,...) not always exhaustive and/or…

Atomic Physics · Physics 2016-06-22 Jean-Christophe Pain , Franck Gilleron , Dominique Gilles

This paper proposes a new large-scale mask-compliant spectral precoder (LS-MSP) for orthogonal frequency division multiplexing systems. In this paper, we first consider a previously proposed mask-compliant spectral precoding scheme that…

Signal Processing · Electrical Eng. & Systems 2019-05-17 Shashi Kant , Gabor Fodor , Mats Bengtsson , Bo Göransson , Carlo Fischione

This study introduces a novel metric, Plan Aperture Modulation (PAM), developed to quantify the modulation of radiotherapy treatment plans. PAM aims to provide a clear geometric interpretation, addressing the limitations of previous…

Medical Physics · Physics 2025-11-25 Victor Hernandez , Iñigo Lara-Aristimuño , Ruben Abella , Jordi Saez

Iron is the dominant heavy element that plays an important role in radiation transport in stellar interiors. Owing to its abundance and large number of bound levels and transitions, iron ions determine the opacity more than any other…

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

A theoretical framework is presented for the computation of rovibrational polaritonic states of a molecule in a lossless infrared (IR) microcavity. In the proposed approach the quantum treatment of the rotational and vibrational motion of…

Chemical Physics · Physics 2023-10-30 Tamás Szidarovszky

A purification algorithm for expanding the single-particle density matrix in terms of the Hamiltonian operator is proposed. The scheme works with a predefined occupation and requires less than half the number of matrix-matrix…

Materials Science · Physics 2009-11-07 Anders M. N. Niklasson

Reconstructing high-quality magnetic resonance images (MRI) from undersampled raw data is of great interest from both technical and clinical point of views. To this date, however, it is still a mathematically and computationally challenging…

Numerical Analysis · Mathematics 2021-09-01 T. Schmoderer , A. I Aviles-Rivero , V. Corona , N. Debroux , C-B. Schönlieb

Implementation of Effective Core Potentials (ECPs) into the molecular scattering suite UKRmol+ is presented together with a set of calculations for a range of targets relevant for plasma modeling. Continuum description in scattering and…

We present a second-order formulation of multi-reference algebraic diagrammatic construction theory [Sokolov, A. Yu. J. Chem. Phys. 2018, 149, 204113] for simulating photoelectron spectra of strongly correlated systems (MR-ADC(2)). The…

Chemical Physics · Physics 2020-07-28 Koushik Chatterjee , Alexander Yu. Sokolov

Improving resolution and sensitivity will widen possible medical applications of magnetic particle imaging. Pulsed excitation promises such benefits, at the cost of more complex hardware solutions and restrictions on drive field amplitude…

In recent years, volumetric modulated arc therapy (VMAT) has been becoming a more and more important radiation technique widely used in clinical application for cancer treatment. One of the key problems in VMAT is treatment plan…

Medical Physics · Physics 2016-01-06 Yu Yang , Bin Dong , Zaiwen Wen

In this article, we examine different approaches for calculating low frequency opacities in the warm dense matter regime. The relevance of the average-atom approximation and of different models for calculating opacities, such as the Ziman…

Plasma Physics · Physics 2025-04-04 Mikael Tacu , Jean-Christophe Pain , Matthias Pautard , Christophe Blancard

Variational formulations of reconstruction in computed tomography have the notable drawback of requiring repeated evaluations of both the forward Radon transform and either its adjoint or an approximate inverse transform which are…

Numerical Analysis · Mathematics 2017-05-23 Richard C. Barnard , Rick Archibald

Here we report new ${\it ab initio}$ calculations of the effective recombination coefficients for the \ion{N}{ii} recombination spectrum. We have taken into account the density dependence of the coefficients arising from the relative…

Solar and Stellar Astrophysics · Physics 2015-05-27 X. Fang , P. J. Storey , X. -W. Liu

We introduce the pCI software package for high-precision atomic structure calculations. The standard method of calculation is based on the configuration interaction (CI) method to describe valence correlations, but can be extended to attain…

Raman spectroscopy is a widely-used non-destructive material characterization method, which provides information about the vibrational modes of the material and therefore of its atomic structure and chemical composition. Interpretation of…

Computational Physics · Physics 2023-02-09 Mohammad Bagheri , Hannu-Pekka Komsa