Output power fluctuations due to different weights of macro particles used in particleincell simulations of Cerenkov devices
Abstract
The output power fluctuations caused by weights of macro particles used in particleincell (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 slowwave 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:
 Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China)
 (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, Email: 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 particleincell simulations of Cerenkov devices. United States: N. p., 2016.
Web. doi:10.1063/1.4958818.
Bao, Rong, Li, Yongdong, Liu, Chunliang, Wang, Hongguang, Email: wanghg@mail.xjtu.edu.cn, & Beijing Vacuum Electronics Research Institute, Beijing 100015. Output power fluctuations due to different weights of macro particles used in particleincell simulations of Cerenkov devices. United States. doi:10.1063/1.4958818.
Bao, Rong, Li, Yongdong, Liu, Chunliang, Wang, Hongguang, Email: 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 particleincell 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 particleincell simulations of Cerenkov devices},
author = {Bao, Rong and Li, Yongdong and Liu, Chunliang and Wang, Hongguang, Email: 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 particleincell (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 slowwave 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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