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Title: A statistical study of gyro-averaging effects in a reduced model of drift-wave transport

Here, a statistical study of finite Larmor radius (FLR) effects on transport driven by electrostatic driftwaves is presented. The study is based on a reduced discrete Hamiltonian dynamical system known as the gyro-averaged standard map (GSM). In this system, FLR effects are incorporated through the gyro-averaging of a simplified weak-turbulence model of electrostatic fluctuations. Formally, the GSM is a modified version of the standard map in which the perturbation amplitude, K 0, becomes K 0J 0($$\hat{p}$$), where J 0 is the zeroth-order Bessel function and $$\hat{p}$$ s the Larmor radius. Assuming a Maxwellian probability density function (pdf) for $$\hat{p}$$ , we compute analytically and numerically the pdf and the cumulative distribution function of the effective drift-wave perturba- tion amplitude K 0J 0($$\hat{p}$$). Using these results, we compute the probability of loss of confinement (i.e., global chaos), P c provides an upper bound for the escape rate, and that P t rovides a good estimate of the particle trapping rate. Lastly. the analytical results are compared with direct numerical Monte-Carlo simulations of particle transport.
Authors:
 [1] ; ORCiD logo [2] ;  [3] ;  [1]
  1. Univ. of Sao Paulo (Brazil)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  3. Humboldt Univ. of Berlin (Germany). Physics Inst.
Publication Date:
Grant/Contract Number:
AC05-00OR22725
Type:
Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 23; Journal Issue: 8; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org:
USDOE Office of Science (SC)
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING
OSTI Identifier:
1333071
Alternate Identifier(s):
OSTI ID: 1306688

Fonseca, Julio, Del-Castillo-Negrete, Diego B., Sokolov, Igor M., and Caldas, Ibere L.. A statistical study of gyro-averaging effects in a reduced model of drift-wave transport. United States: N. p., Web. doi:10.1063/1.4961430.
Fonseca, Julio, Del-Castillo-Negrete, Diego B., Sokolov, Igor M., & Caldas, Ibere L.. A statistical study of gyro-averaging effects in a reduced model of drift-wave transport. United States. doi:10.1063/1.4961430.
Fonseca, Julio, Del-Castillo-Negrete, Diego B., Sokolov, Igor M., and Caldas, Ibere L.. 2016. "A statistical study of gyro-averaging effects in a reduced model of drift-wave transport". United States. doi:10.1063/1.4961430. https://www.osti.gov/servlets/purl/1333071.
@article{osti_1333071,
title = {A statistical study of gyro-averaging effects in a reduced model of drift-wave transport},
author = {Fonseca, Julio and Del-Castillo-Negrete, Diego B. and Sokolov, Igor M. and Caldas, Ibere L.},
abstractNote = {Here, a statistical study of finite Larmor radius (FLR) effects on transport driven by electrostatic driftwaves is presented. The study is based on a reduced discrete Hamiltonian dynamical system known as the gyro-averaged standard map (GSM). In this system, FLR effects are incorporated through the gyro-averaging of a simplified weak-turbulence model of electrostatic fluctuations. Formally, the GSM is a modified version of the standard map in which the perturbation amplitude, K0, becomes K0J0($\hat{p}$), where J0 is the zeroth-order Bessel function and $\hat{p}$ s the Larmor radius. Assuming a Maxwellian probability density function (pdf) for $\hat{p}$ , we compute analytically and numerically the pdf and the cumulative distribution function of the effective drift-wave perturba- tion amplitude K0J0($\hat{p}$). Using these results, we compute the probability of loss of confinement (i.e., global chaos), Pc provides an upper bound for the escape rate, and that Pt rovides a good estimate of the particle trapping rate. Lastly. the analytical results are compared with direct numerical Monte-Carlo simulations of particle transport.},
doi = {10.1063/1.4961430},
journal = {Physics of Plasmas},
number = 8,
volume = 23,
place = {United States},
year = {2016},
month = {8}
}