Resonance frequency broadening of waveparticle interaction in tokamaks due to Alfvénic eigenmode
Abstract
We use the guiding center code ORBIT to study the broadening of resonances and the parametric dependence of the resonance frequency broadening width $$\Delta\Omega$$ on the nonlinear particle trapping frequency $$\omega_b$$ of waveparticle interaction with specific examples using realistic equilibrium DIIID shot 159243 (Collins et al. 2016 Phys. Rev. Lett. 116 095001). When the mode amplitude is small, the pendulum approximation for energetic particle dynamics near the resonance is found to be applicable and the ratio of the resonance frequency width to the deeply trapped bounce frequency $$\Delta\Omega/\omega_b$$ equals 4, as predicted by theory. Lastly, it is found that as the mode amplitude increases, the coefficient $$a=\Delta\Omega/\omega_b$$ becomes increasingly smaller because of the breaking down of the nonlinear pendulum approximation for the waveparticle interaction.
 Authors:
 Peking Univ., Beijing (China). School of Physics, Fusion Simulation Center and State Key Lab. of Nuclear Physics and Technology
 Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
 Univ. of Texas, Austin, TX (United States). Inst. for Fusion Studies
 Harbin Inst. of Technology (China)
 Publication Date:
 Research Org.:
 Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
 Sponsoring Org.:
 USDOE; National Natural Science Foundation of China (NNSFC)
 OSTI Identifier:
 1425207
 Grant/Contract Number:
 2012/228302; 2014/032894; JCKY2016212A505; AC0209CH11466; FC0204ER54698; 2013GB11001; 2014GB107004; 11261140326; 41674165
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Nuclear Fusion
 Additional Journal Information:
 Journal Name: Nuclear Fusion; Journal ID: ISSN 00295515
 Publisher:
 IOP Science
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; waveparticle interaction; RSAE; DIIID; Resonance broadening
Citation Formats
Meng, Guo, Gorelenkov, Nikolai N., Duarte, Vinicius N., Berk, Herb L., White, Roscoe B., and Wang, Xiaogang. Resonance frequency broadening of waveparticle interaction in tokamaks due to Alfvénic eigenmode. United States: N. p., 2018.
Web. doi:10.1088/17414326/aaa918.
Meng, Guo, Gorelenkov, Nikolai N., Duarte, Vinicius N., Berk, Herb L., White, Roscoe B., & Wang, Xiaogang. Resonance frequency broadening of waveparticle interaction in tokamaks due to Alfvénic eigenmode. United States. doi:10.1088/17414326/aaa918.
Meng, Guo, Gorelenkov, Nikolai N., Duarte, Vinicius N., Berk, Herb L., White, Roscoe B., and Wang, Xiaogang. 2018.
"Resonance frequency broadening of waveparticle interaction in tokamaks due to Alfvénic eigenmode". United States.
doi:10.1088/17414326/aaa918.
@article{osti_1425207,
title = {Resonance frequency broadening of waveparticle interaction in tokamaks due to Alfvénic eigenmode},
author = {Meng, Guo and Gorelenkov, Nikolai N. and Duarte, Vinicius N. and Berk, Herb L. and White, Roscoe B. and Wang, Xiaogang},
abstractNote = {We use the guiding center code ORBIT to study the broadening of resonances and the parametric dependence of the resonance frequency broadening width $\Delta\Omega$ on the nonlinear particle trapping frequency $\omega_b$ of waveparticle interaction with specific examples using realistic equilibrium DIIID shot 159243 (Collins et al. 2016 Phys. Rev. Lett. 116 095001). When the mode amplitude is small, the pendulum approximation for energetic particle dynamics near the resonance is found to be applicable and the ratio of the resonance frequency width to the deeply trapped bounce frequency $\Delta\Omega/\omega_b$ equals 4, as predicted by theory. Lastly, it is found that as the mode amplitude increases, the coefficient $a=\Delta\Omega/\omega_b$ becomes increasingly smaller because of the breaking down of the nonlinear pendulum approximation for the waveparticle interaction.},
doi = {10.1088/17414326/aaa918},
journal = {Nuclear Fusion},
number = ,
volume = ,
place = {United States},
year = 2018,
month = 1
}

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