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Large Scale Earth's Bow Shock with Northern IMF as Simulated by pic code in Parallel with MHD Model

JOURNAL OF ASTROPHYSICS AND ASTRONOMY 2016年第2期37卷 1页

作者： Baraka, Suleiman Natl Inst Aerosp 100 Explorat Way Hampton VA USA Al Aqsa Univ Ctr Astron & Space Sci CASSR POB 4051 Gaza Israel Inst Astrophys 98 Bis Blvd Arago F-75015 Paris France

In this paper, we propose a 3D kinetic model (particle-in-cell, pic) for the description of the large scale Earth's bow shock. The proposed version is stable and does not require huge or extensive computer resources. Because pic simulations work with scaled plasma and field parameters, we also propose to validate our code by comparing its results with the available MHD simulations under same scaled solar wind (SW) and (IMF) conditions. We report new results from the two models. In both codes the Earth's bow shock position is found to be approximate to 14.8R(E) along the Sun-Earth line, and approximate to 29RE on the dusk side. Those findings are consistent with past in situ observations. Both simulations reproduce the theoretical jump conditions at the shock. However, the pic code density and temperature distributions are inflated and slightly shifted sunward when compared to the MHD results. Kinetic electron motions and reflected ions upstream may cause this sunward shift. Species distributions in the foreshock region are depicted within the transition of the shock (measured approximate to 2c/omega(pi) for Theta(Bn) = 90 degrees and M-MS = 4.7) and in the downstream. The size of the foot jump in the magnetic field at the shock is measured to be (1.7c/omega(pi)). In the foreshocked region, the thermal velocity is found equal to 213 km s(-1) at 15R(E) and is equal to 63 km s(-1) at 12 R-E (magnetosheath region). Despite the large cell size of the current version of the pic code, it is powerful to retain macrostructure of planets magnetospheres in very short time, thus it can be used for pedagogical test purposes. It is also likely complementary with MHD to deepen our understanding of the large scale magnetosphere.

关键词： Magnetosphere magnetopause bow shock pic code MHD model

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Stochastic heating in ultra high intensity laser-plasma interaction:: Theory and pic code simulations

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LASER AND PARTICLE BEAMS 2006年第2期24卷 223-230页

作者： Patin, D. Lefebvre, E. Bourdier, A. D'Humières, E. CEA DAM Lle France Dept Phys Theor & Applicat F-91680 Bruyeres Le Chatel France

In the first part, the theoretical model of the stochastic heating effect is presented briefly. Then, a numerical resolution of the Hamilton equations highlights the threshold of the stochastic effect. Finally, Particle-In-Cell (pic) code simulations results, for experimentally relevant parameters, are presented in order to confirm the acceleration mechanism predicted by the one-particle theoretical model. This paper gives the conditions on the different experimental parameters in order to have an optimization of the stochastic heating.

关键词： laser-plasma interaction pic code stochastic heating

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Interconnection between hydro and pic codes for fast ignition simulations

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LASER AND PARTICLE BEAMS 2004年第1期22卷 41-44页

作者： Sakagami, H Mima, K Himeji Inst Technol Himeji Hyogo 6712001 Japan Osaka Univ Inst Laser Engn Suita Osaka 565 Japan

Relativistic laser-plasma interaction, subsequent superhot electron transport, superhot electron energy deposition, and the overall implosion process are key subjects for fast ignition. All these phenomena couple with each other, and more studies by simulations are essential. We have a plan to simulate the whole of fast ignition self-consistently with four individual codes. Four codes are integrated into one big system in the Fast Ignition Integrated Interconnecting code project. In a first stage of this project, we integrate the Arbitrary Lagrangian Eulerian (ALE) hydro code with the collective particle in cell (pic) code. The pic code obtains density profile at maximum compression from the ALE hydro code to introduce imploded plasma into a pic system, and we can simulate interaction between ignition laser and realistic plasma. We have evaluated reflected laser spectrum and electron energy distribution, and found many differences between the realistic plasma profile and the conventional one in pic simulations.

关键词： fast ignition hydro code interconnection pic code simulation

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Implementation of parallel plasma particle-in-cell codes on PC cluster

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COMPUTER PHYSICS COMMUNICATIONS 2001年第1期135卷 93-104页

作者： Lu, QM Cai, DS Univ Sci & Technol China Dept Earth & Space Sci Hefei 230026 Anhui Peoples R China Univ Tsukuba Inst Informat Sci & Elect Tsukuba Ibaraki 305 Japan

Plasma particle-in-cell (pic) codes model the interaction of charged particles with the surrounding fields, and they have been implemented on many advanced parallel computers. Recently, many PC clusters which consist of inexpensive PCs have been developed to do parallel computing, and we also build such a PC cluster. In this paper, we present the implementation of a parallel plasma pic code on our PC cluster using MPI, PGHPF and JavaMPI. (C) 2001 Elsevier Science B.V. All rights reserved.

关键词： pic code PC cluster MPI PGHPF Java

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A method for obtaining three-dimensional computational equilibrium of non-neutral plasmas using WARP

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JOURNAL OF COMPUTATIONAL PHYSICS 2007年第2期225卷 1736-1752页

作者： Gomberoff, K. Wurtele, J. Friedman, A. Grote, D. P. Vay, J. -L. Univ Calif Berkeley Lawrence Berkeley Lab Ctr Beam Phys Berkeley CA 94720 USA Univ Calif Berkeley Dept Phys Berkeley CA 94720 USA Lawrence Livermore Natl Lab Fus Energy Program Livermore CA 94550 USA

Computer simulation studies of the stability and transport properties of trapped non-neutral plasmas require the numerical realization of a three-dimensional plasma distribution. This paper presents a new numerical method for obtaining, without an explicit model for physical collisions in the code, a low noise three-dimensional computational equilibrium distribution. This requires both the loading of particles into an idealized distribution and the relaxation from that distribution toward an approximate numerical equilibrium. The equilibrium can then be modified through a slow change of system parameters, to generate other equilibria. In the present, work we apply this method to a UC Berkeley experiment on electron confinement in magnetic geometries appropriate for the ALPHA anti-hydrogen experiment, using the three-dimensional particle-in-cell code WARP. WARP's guiding center mover and its option to switch between different solvers during a simulation are highly valuable because they speed up the simulations;they enable the practical use of the new technique for generating numerical equilibrium states of trapped non-neutral plasmas. (c) 2007 Elsevier Inc. All rights reserved.

关键词： WARP pic code particle-in-cell equilibrium numerical equilibrium non-neutral plasmas plasma trap numerical collisions three dimensional non-uniform field

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Three-dimensional particle-in-cell simulation of 10-vane strapped magnetron oscillator

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IEEE TRANSACTIONS ON PLASMA SCIENCE 2004年第5期32卷 2099-2104页

作者： Kim, JI Won, JH Ha, HJ Shon, JC Park, GS Seoul Natl Univ Sch Phys Seoul 151742 South Korea Samsung Elect Suwon 443742 South Korea

The performance of a 10-vane strapped magnetron oscillator used in microwave ovens was benchmarked using the three-dimensional particle-in-cell (pic) code MAGIC3D. The formation of the five electron spokes in the oscillation region confirms the pi-mode oscillation of a 10-vane strapped resonator showing its mode separation with the adjacent mode to be 82%. The measured operating frequency of 2.465 GHz and the saturated output power of 1.04 kW are in good agreement with the simulated values of 2.470 GHz and 1.07 kW, respectively. The magnetron with an efficiency of 75% is operated at the beam voltage of 4.3 kV, the anode current. of 0.33 A, and the cathode current of 1.08 A when the external axial magnetic field of 0.19 T is applied. In addition, the measured harmonic components of the radiated output are compared with the simulated one estimated by Fourier transformation of an induced radio-frequency voltage signal, showing good agreement.

关键词： MAGIC3D oscillator pic code 10-vane strapped magnetron

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Three-dimensional simulation of laser-plasma-based electron acceleration

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PRAMANA-JOURNAL OF PHYSICS 2012年第4期78卷 613-623页

作者： Upadhyay, A. Patel, K. Rao, B. S. Naik, P. A. Gupta, P. D. Raja Ramanna Ctr Adv Technol Laser Plasma Div Indore 452013 Madhya Pradesh India Bhabha Atom Res Ctr Div Laser & Plasma Technol Bombay 400085 Maharashtra India

A sequential three-dimensional (3D) particle-in-cell simulation code picPSI-3D with a user friendly gaphical user interface (GUI) has been developed and used to study the interaction of plasma with ultrahigh intensity laser radiation. A case study of laser plasma-based electron acceleration has been carried out to assess the performance of this code. Simulations have been performed for a Gaussian laser beam of peak intensity 5 x 10(19) W/cm(2) propagating through an underdense plasma of uniform density 1 x 10(19) cm(-3), and for a Gaussian laser beam of peak intensity 1.5 x 10(19) W/cm(2) propagating through an underdense plasma of uniform density 3.5 x 10(19) cm(-3). The electron energy spectrum has been evaluated at different time-steps during the propagation of the laser beam. When the plasma density is 1 x 10(19) cm(-3), simulations show that the electron energy spectrum forms a monoenergetic peak at similar to 14 MeV, with an energy spread of +/- 7 MeV. On the other hand, when the plasma density is 3.5 x 10(19) cm(-3), simulations show that the electron energy spectrum forms a monoenergetic peak at similar to 23 MeV, with an energy spread of +/- 7.5 MeV.

关键词： Laser-plasma simulation pic code electron acceleration

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Particle-in-cell plasma simulation on heterogeneous cluster systems

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JOURNAL OF COMPUTATIONAL SCIENCE 2012年第6期3卷 474-479页

作者： Bastrakov, S. Donchenko, R. Gonoskov, A. Efimenko, E. Malyshev, A. Meyerov, I. Surmin, I. Lobachevsky State Univ Nizhni Novgorod Nizhnii Novgorod Russia Russian Acad Sci Inst Appl Phys Nizhnii Novgorod Russia

This paper offers an approach to high-performance implementation of the Particle-in-Cell (pic) algorithm for GPU-enabled heterogeneous cluster systems. We present picador a tool for three dimensional plasma simulation based on the fully relativistic pic algorithm aimed at research of high intensity laser-matter interaction. It scales up to at least 2048 CPU cores with 85% strong scaling efficiency and 512 GPUs with 64% weak scaling efficiency, achieving up to 28% of the peak performance on the CPU and 14% on the CPU, respectively. (C) 2012 Elsevier B.V. All rights reserved.

关键词： pic code Large-scale simulation Scalabilty analysis GPU optimization Supercell

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Suppressing the numerical Cherenkov radiation in the Yee numerical scheme

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JOURNAL OF COMPUTATIONAL PHYSICS 2016年 305卷 664-676页

作者： Nuter, Rachel Tikhonchuk, Vladimir Univ Bordeaux CNRS CEA CELIAUMR 5107 F-33405 Talence France

The next generation of laser facilities will routinely produce relativistic particle beams from the interaction of intense laser pulses with solids and/or gases. Their modeling with Particle-In-Cell (pic) codes needs dispersion-free Maxwell solvers in order to properly describe the interaction of electromagnetic waves with relativistic particles. A particular attention is devoted to the suppression of the numerical Cherenkov instability, responsible for the noise generation. It occurs when the electromagnetic wave is artificially slowed down because of the finite mesh size, thus allowing for the high energy particles to propagate with super-luminous velocities. In the present paper, we show how a slight increase of the light velocity in the Maxwell's equations enables to suppress this instability while keeping a good overall precision of calculations. (C) 2015 Elsevier Inc. All rights reserved.

关键词： pic code Kinetic models Collisionless shock Numerical Cherenkov instability

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Validation of 3-D Time Domain Particle-in-Cell Simulations for Cold Testing a W-Band Gyrotron Cavity

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IEEE TRANSACTIONS ON PLASMA SCIENCE 2014年第12期42卷 3989-3995页

作者： Sawant, Ashwini Kim, Sung Gug Lin, Ming-Chieh Kim, Jung Ho Hong, Yongjun So, Joonho Choi, EunMi Ulsan Natl Inst Sci & Technol Sch Elect & Comp Engn Ulsan 689798 South Korea Hanyang Univ Dept Elect & Biomed Engn Seoul 151742 South Korea LIG Nex1 Co Ltd Songnam 463400 South Korea Agcy Def Dev Taejon 305152 South Korea Ulsan Natl Inst Sci & Technol Sch Elect & Comp Engn Dept Phys Ulsan 689798 South Korea

This paper evaluates the performance and reliability of a commercially available 3-D conformal finite-difference time-domain particle-in-cell (pic) code, VSim, for cold test simulations of a gyrotron cavity. An interaction cavity for a 95-GHz gyrotron is simulated and optimized using the VSim pic code to achieve TE6,2 mode excitation. The optimized cavity design is also studied and compared using the commercially available numerical code, CASCADE, and pic code, MAGIC. A rigorous analysis of the simulation results obtained through VSim and MAGIC is performed using the CASCADE results as a reference. The performance of VSim is also compared with MAGIC based on its accuracy for calculating the resonant frequency and quality factor. Finally, the optimized cavity is fabricated and experimentally tested to measure the resonant frequency and the quality factor. The experimental results confirm the reliability and accuracy of the VSim cold cavity results.

关键词： Conformal finite-difference time-domain (CFDTD) simulation gyrotron cavity MAGIC pic code VSim

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