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We present the first two-dimensional (2D) optical Thomson scattering measurements of electron density and temperature in laser-produced plasmas. The novel instrument directly measures $n_e(x,y)$ and $T_e(x,y)$ in two dimensions over large…

Instrumentation and Detectors · Physics 2023-09-12 H. Zhang , J. J. Pilgram , C. G. Constantin , L. Rovige , P. V. Heuer , S. Ghazaryan , M. Kaloyan , R. S. Dorst , D. B. Schaeffer , C. Niemann

A multispecies, collisionless plasma is modeled by the Vlasov-Poisson system. Assuming that the electric field decays with sufficient rapidity as $t \to\infty$, we show that the velocity characteristics and spatial averages of the particle…

Analysis of PDEs · Mathematics 2022-01-25 Stephen Pankavich

In this paper we address the problem of estimating the posterior distribution of the static parameters of a continuous time state space model with discrete time observations by an algorithm that combines the Kalman filter and a particle…

Computation · Statistics 2019-05-22 Jian He , Asma Khedher , Peter Spreij

Vehicular communication channels are characterized by a non-stationary time- and frequency-selective fading process due to rapid changes in the environment. The non-stationary fading process can be characterized by assuming local…

Networking and Internet Architecture · Computer Science 2014-04-28 Laura Bernadó , Thomas Zemen , Fredrik Tufvesson , Andreas F. Molisch , Christoph F. Mecklenbräuker

We discuss the distributed matching scheme in accelerators where control of transverse beam phase space, oscillation, and transport is accomplished by flexible distribution of focusing elements beyond dedicated matching sections. Besides…

Accelerator Physics · Physics 2018-08-07 Yu-Chiu Chao

The fractional Poisson process (FPP) generalizes the standard Poisson process by replacing exponentially distributed return times with Mittag-Leffler distributed ones with an extra tail parameter, allowing for greater flexibility. The FPP…

Applications · Statistics 2025-11-12 Merle Mendel , Roland Fried

Time--distance inversions usually provide tomographic maps of the interesting plasma properties (we will focus on flows) at various depths. These maps however do not correspond directly to the flow field, but rather to the true flow field…

Solar and Stellar Astrophysics · Physics 2017-04-12 M. Svanda , M. Kozon

We present a variationally separable splitting technique for the generalized-$\alpha$ method for solving parabolic partial differential equations. We develop a technique for a tensor-product mesh which results in a solver with a linear cost…

Numerical Analysis · Mathematics 2018-11-26 Pouria Behnoudfar , Victor M. Calo , Quanling Deng , Peter D. Minev

Thermodynamic characteristics of the radiation of condensed combustion products presented in the form of agglomerates of metal-oxide nanoparticles demonstrate deviations from the classical Planck's law. We propose to interpret these…

Plasma Physics · Physics 2022-03-29 G. S. Dragan , V. V. Kutarov , A. Y. Bekshaev

We study a simple modification to the conventional time of flight mass spectrometry (TOFMS) where a \emph{variable} and (pseudo)-\emph{random} pulsing rate is used which allows for traces from different pulses to overlap. This modification…

Optimization and Control · Mathematics 2013-07-30 Morteza Ibrahimi , Andrea Montanari , George S Moore

The results obtained by the plasma physics community for the validation and the prediction of turbulence and transport in magnetized plasma come mainly from the use of very CPU-consuming particle-in-cell or (gyro)kinetic codes which…

Plasma Physics · Physics 2017-05-24 Olivier Izacard

Systematic discrepancies between electron temperature (Te) measurements from radially viewing electron cyclotron emission (ECE) and Thomson scattering (TS) diagnostics have been observed in multiple tokamaks and are widely attributed to…

Plasma Physics · Physics 2026-05-06 Saeid Houshmandyar , William L. Rowan

A Statistic Vectorial Complex Ray Model (SVCRM) is proposed for the scattering of a plane wave by a non-spherical dielectric particle in three dimensions. This method counts the complex amplitudes of all rays arriving in a tiny box in the…

Optics · Physics 2024-03-21 Ruiping Yang , Bing Wei , Claude Rozé , Saïd Idlahcen , Kuan Ffang Ren

The calculation of the point vortex velocity probability distribution function (vvpdf) is extended to a larger class of systems beyond the nonconserved TDGL model treated earlier. The range is extended to include certain anisotropic models…

Soft Condensed Matter · Physics 2009-11-10 Gene F. Mazenko

Recent advances in laser technology allow us to follow electronic motion at its natural time-scale with ultra-fast time resolution, leading the way towards attosecond physics experiments of extreme precision. In this work, we assess the use…

Other Condensed Matter · Physics 2016-06-22 Jessica Walkenhorst , Umberto De Giovannini , Alberto Castro , Angel Rubio

We propose a nonparametric density estimator based on the Gaussian process (GP) and derive three novel closed form learning algorithms based on Fisher divergence (FD) score matching. The density estimator is formed by multiplying a base…

Machine Learning · Computer Science 2025-11-17 John Paisley , Wei Zhang , Brian Barr

Diffusion models produce high-quality synthetic data but suffer from slow inference. We propose 3D Variable-Step Denoising Diffusion Probabilistic Model (VS-DDPM) a framework engineered to maintain generative quality while accelerating…

Computer Vision and Pattern Recognition · Computer Science 2026-05-12 Nikoo Moradi , Gijs Luijten , Behrus Hinrichs-Puladi , Jens Kleesiek , Victor Alves , Jan Egger , André Ferreira

The particle filter (PF), also known as sequential Monte Carlo (SMC), approximates high-dimensional probability distributions and their normalizing constants in the discrete-time setting. To reduce the variance of the Monte Carlo…

Computation · Statistics 2026-05-05 Jianfeng Lu , Yuliang Wang

Diffusion Probabilistic Field (DPF) models the distribution of continuous functions defined over metric spaces. While DPF shows great potential for unifying data generation of various modalities including images, videos, and 3D geometry, it…

Computer Vision and Pattern Recognition · Computer Science 2023-05-25 Kangfu Mei , Mo Zhou , Vishal M. Patel

Synthetic data generation is an important tool for privacy-preserving data sharing. Although diffusion models have set recent benchmarks, flow matching (FM) offers a promising alternative. This paper presents different ways to implement FM…

Machine Learning · Computer Science 2026-03-18 Bahrul Ilmi Nasution , Floor Eijkelboom , Mark Elliot , Richard Allmendinger , Christian A. Naesseth