CC BY
41114
Секция 6
Список литературы
1. Ю.Г. Соловейчик, М.Э. Рояк, М.Г. Персова. Метод конечных элементов для решения скалярных и векторных задач. - Новосибирск: НГТУ, 2007. - 899 с.
2. Bossavit A. Computational Electromagnetism: Variational Formulations, Complementarity, Edge Elements. Academic Press, 1998, 352pp.
Гибридные численные модели ионно-звуковых ударных волн в многокомпонентной плазме
А. А. Ефимова, Г. И. Дудникова
Институт вычислительной математики и математической геофизики СО РАН
Email: [email protected]
DOI: 10.24411/9999-017A-2019-10235
Генерация продольных электростатических ионно-звуковых волн в плазме возможна только в том случае, когда температура электронов значительно превышает температуру ионов [1]. Подобные условия являются типичными для плазмы солнечного ветра и часто реализуются в лабораторных экспериментах как по нагреву и удержанию плазмы, так и по ускорению частиц при взаимодействии лазерного импульса с плазмой [2]. В реальности в плазме обычно присутствуют ионы различных сортов. Многокомпонентный состав ионов приводит к существенному изменению структуры ударной волны и механизмов ускорения заряженных частиц во фронте волны. В данной работе представлены одномерные гибридные численные модели генерации ионно-звуковых ударных волн в многокомпонентной плазме, основанные на кинетическом приближении только для ионной компоненты плазмы. Для решения уравнений Власова используется метод частиц-в-ячейках. Исследована эволюция локализованного возмущения плотности плазмы произвольной амплитуды в зависимости от типа и процентного содержания ионных компонент и функции распределения электронов. Получены оценки применимости гибридных моделей для описания закритических режимов генерируемых ударных волн.
Работа выполнена при финансовой поддержке Российского фонда фундаментальных исследований (код проекта 18-29-21025).
Список литературы
1. Сагдеев Р. З. Коллективные процессы и ударные волны в разреженной плазме. / Вопросы теории плазмы. Под редакцией М. А. Леонтовича. Москва: Атомиздат, 1964. — Выпуск 4., С. 20-80.
2. Malkov M. A., Sagdeev R. Z., Dudnikova, G. I., et al. Ion-acoustic shocks with self-regulated ion reflection and acceleration // Physics of Plasmas, 2016. — Volume 23, Issue 4, P. 043105.
Boundary element method in 3D problems of mathematical physics
V. Ya. Ivanov
Institute of Computational Technologies SB RAS
Email: [email protected]
DOI: 10.24411/9999-017A-2019-10236
Numerical algorithms of the boundary problems described by Laplace, Poisson, Helmholtz and Maxwell equations based on the integral representations are described. Combinations of single-layer, double-layer and volume potentials are used to represent the solution. Analytical technique of singularity extraction is used to obtain precision and stable numerical solutions for a potential and its high-order derivatives [1]. The numerous examples of test problems and applications to the precision problems of electron optics, accelerator physics and plasma-beam interaction are demonstrated [2-7]. The original algorithms can be used for the problems of analysis, optimization and synthesis of physical electronic devices [8]. Decomposition algorithms to solve complex three-dimensional problems are presented [9].
References
1. Ivanov V, Kriklivyy V. Numerical algorithms for boundary problems with disturbed axial symmetry. NIM A. 2004; 519: 96-116.
2. Ivanov V, Teryaev V, Karliner M, Yakovlev V. Application of the method of boundary integral equations for the calculation of high-frequency resonators. Zhurnal Vychislitelnoi Matematiki I Matematicheskoi Fiziki. 1986; 12 :.1900-1905. In Russian.
Математическое моделирование в задачах геофизики и электрофизики 115
3. Ivanov V. Green's Function Technique in Forming of Intensive Beams. Int. J. of Modern Physics A, 2009; 24(5): 869-878.
4. Ivanov V. Analytical Technique in the Boundary Element Method for 3D Problems of Electron Optics. Microscopy & Microanalysis. 2015; 21(4): 236-241.
5. Ivanov V. The method of analysis of three-dimensional non stationary flows of charged particle. In: Numerical analysis. In: Proc. Inst. of Mathematics SB RAS. Novosibirsk, Nauka. 1989; 15: 172-187. In Russian.
6. Ivanov V, Krasnykh A. Analytical computations in solution of 3D problems of physical electronics by BEM. In: Proceedings of the ACES-2002, March 18-22, 2002, Monterey, CA.
7. Ivanov V, Krasnykh A. Scheitrum G, Sprehn D, Ives L, Miram G. 3D modeling activity for novel high power electron guns at SLAC. In: Proceedings of the Particle Accelerator Conference (PAC 03), Portland, Oregon, 12-16 May 2003: 3312-3314.
8. V. Ivanov. Computational methods, optimization and synthesis in electron optics.- Hmbg: Palmarium Academic Publishing, 2016.-525 pp.
9. Ivanov V. Decomposition method for complex 3D problems in electron optics. J. of Physical Science & Applications. 2015; 5(2): 96-100.
Micrichannel amplifier behavior in strong magnetic field
V. Ya. Ivanov
Institute of Computational Technologies SB RAS
Email: vivanov. [email protected]
DOI: 10.24411/9999-017A-2019-10237
Microchannel plate photomultiplier tubes (MCP PMT) can work in a high magnetic field and have an excellent time resolution. The influence of the magnetic fields up to 4.5 T on the parameters of several MCP PMTs of different designs was investigated. PMTs with two, three and four MCPs were simulated and tested in magnetic fields. Description of mathematical models for fast photo detectors based on microchannel plates (MCP) in three-dimensional formulation is given [1-6]. The models include calculations of photoelectron collection efficiency in the gap photo cathode - MCP, gain factor of secondary electron cascades in the channels, the particle scattering in the gaps between the plates, taking into account the fringe fields and strong external magnetic fields. Comparisons of numerical and experimental data are given [7-11]. The dependencies of major device parameters vs. of applied voltage, pore size, and magnetic field magnitude have been studied. Dependencies of the time resolution, the gain and the photoelectron collection efficiency on the magnetic field are presented.
This work was (partially) supported by the Russian Science Foundation (Project no.16-12-10221). References
1. B.Adams, K.Attenkofer, H.Frish, Z.Insepov, VIvanov et al. A Brief Technical History of the Large-Area Picosecond Photodetector (LAPPD) Collaboration. 2016.- 45 pp.
2. V.Ivanov et al. Numerical simulations of fast photo detectors based on microchannel plates //12th International Conf. "Instrumentation for Colliding Beam Physics" INSTR-2017, February 27 - March 3, 2017, Novosibirsk..
3. V.Ivanov. The review of mathematical models for three-dimensional problems of electron optics. Int. Conf. on Atomic and Nuclear Physics, July 23-25, 2018, Osaka, Japan.
4. V.Ivanov. Computer design of microchannel amplifiers. Scholars' Press, 2018, 220 pp.
5. V.Ivanov.. Taking into account the fringe fields in microchannel amplifier design//Open Academic J. of Advanced Science and Technology, 1, N1 (2017). P.42-44.
6. V.Ivanov., I. Turchanocsky. Influence of the fringe fields in microchannel amplifier design// American J. of Modern Physics, 7, 1(2017) pp.31-33.
7. V. Ivanov, A. Barnyakov, M. Barnyakov, V. Bobrovnikov, I. Ovtin. Numerical simulations of fast photo detectors based on microchannel plates // J of Instrumentation, 12 (2017) P09024.
8. A. Barnyakov et al. On measurements of photoelectron collection efficiency in MCP based PMTs // J of Instrumentation, 12 (2017) P09036.
9. V.Ivanov, A.Barnyakov, M.Barnyakov. Calibration procedure in microchannel amplifiers design, NIM A 903 (2018) 170-174.
10. V.Ivanov, A.Barnyakov, M.Barnyakov, VBlinov, VBobrovsky, I.Ovtin. Methodology of computer design of photodetectors based on microchannel plates. Int. Conf. on Atomic and Nuclear Physics, July 23-25, 2018, Osaka, Japan.
11. M. Barnyakov, A. Barnyakov, V Blinov, V. Bobrovnikov, A. Bykov; V. Ivanov, A. Katcin, E. Mamoshkina, I. Ovtin, K. Petrukhin, S. Pivovarov, V. Prisekin, E. Pyata. Development of a picosecond MCP based particle detector, NIM A (2018) 01 057.
