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Title: Output power fluctuations due to different weights of macro particles used in particle-in-cell simulations of Cerenkov devices

Abstract

The output power fluctuations caused by weights of macro particles used in particle-in-cell (PIC) simulations of a backward wave oscillator and a travelling wave tube are statistically analyzed. It is found that the velocities of electrons passed a specific slow-wave structure form a specific electron velocity distribution. The electron velocity distribution obtained in PIC simulation with a relative small weight of macro particles is considered as an initial distribution. By analyzing this initial distribution with a statistical method, the estimations of the output power fluctuations caused by different weights of macro particles are obtained. The statistical method is verified by comparing the estimations with the simulation results. The fluctuations become stronger with increasing weight of macro particles, which can also be determined reversely from estimations of the output power fluctuations. With the weights of macro particles optimized by the statistical method, the output power fluctuations in PIC simulations are relatively small and acceptable.

Authors:
; ;  [1];  [1];  [2]
  1. Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China)
  2. (China)
Publication Date:
OSTI Identifier:
22600026
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CHERENKOV COUNTERS; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; DISTRIBUTION; ELECTRONS; FLUCTUATIONS; PARTICLES; TRAVELLING WAVE TUBES; TRAVELLING WAVES; VELOCITY; WEIGHT

Citation Formats

Bao, Rong, Li, Yongdong, Liu, Chunliang, Wang, Hongguang, E-mail: wanghg@mail.xjtu.edu.cn, and Beijing Vacuum Electronics Research Institute, Beijing 100015. Output power fluctuations due to different weights of macro particles used in particle-in-cell simulations of Cerenkov devices. United States: N. p., 2016. Web. doi:10.1063/1.4958818.
Bao, Rong, Li, Yongdong, Liu, Chunliang, Wang, Hongguang, E-mail: wanghg@mail.xjtu.edu.cn, & Beijing Vacuum Electronics Research Institute, Beijing 100015. Output power fluctuations due to different weights of macro particles used in particle-in-cell simulations of Cerenkov devices. United States. doi:10.1063/1.4958818.
Bao, Rong, Li, Yongdong, Liu, Chunliang, Wang, Hongguang, E-mail: wanghg@mail.xjtu.edu.cn, and Beijing Vacuum Electronics Research Institute, Beijing 100015. 2016. "Output power fluctuations due to different weights of macro particles used in particle-in-cell simulations of Cerenkov devices". United States. doi:10.1063/1.4958818.
@article{osti_22600026,
title = {Output power fluctuations due to different weights of macro particles used in particle-in-cell simulations of Cerenkov devices},
author = {Bao, Rong and Li, Yongdong and Liu, Chunliang and Wang, Hongguang, E-mail: wanghg@mail.xjtu.edu.cn and Beijing Vacuum Electronics Research Institute, Beijing 100015},
abstractNote = {The output power fluctuations caused by weights of macro particles used in particle-in-cell (PIC) simulations of a backward wave oscillator and a travelling wave tube are statistically analyzed. It is found that the velocities of electrons passed a specific slow-wave structure form a specific electron velocity distribution. The electron velocity distribution obtained in PIC simulation with a relative small weight of macro particles is considered as an initial distribution. By analyzing this initial distribution with a statistical method, the estimations of the output power fluctuations caused by different weights of macro particles are obtained. The statistical method is verified by comparing the estimations with the simulation results. The fluctuations become stronger with increasing weight of macro particles, which can also be determined reversely from estimations of the output power fluctuations. With the weights of macro particles optimized by the statistical method, the output power fluctuations in PIC simulations are relatively small and acceptable.},
doi = {10.1063/1.4958818},
journal = {Physics of Plasmas},
number = 7,
volume = 23,
place = {United States},
year = 2016,
month = 7
}
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