skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Laboratory study of avalanches in magnetized plasmas

; ; ;
Publication Date:
Sponsoring Org.:
OSTI Identifier:
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review E
Additional Journal Information:
Journal Volume: 91; Journal Issue: 3; Journal ID: ISSN 1539-3755
American Physical Society
Country of Publication:
United States

Citation Formats

Van Compernolle, B., Morales, G. J., Maggs, J. E., and Sydora, R. D. Laboratory study of avalanches in magnetized plasmas. United States: N. p., 2015. Web. doi:10.1103/PhysRevE.91.031102.
Van Compernolle, B., Morales, G. J., Maggs, J. E., & Sydora, R. D. Laboratory study of avalanches in magnetized plasmas. United States. doi:10.1103/PhysRevE.91.031102.
Van Compernolle, B., Morales, G. J., Maggs, J. E., and Sydora, R. D. 2015. "Laboratory study of avalanches in magnetized plasmas". United States. doi:10.1103/PhysRevE.91.031102.
title = {Laboratory study of avalanches in magnetized plasmas},
author = {Van Compernolle, B. and Morales, G. J. and Maggs, J. E. and Sydora, R. D.},
abstractNote = {},
doi = {10.1103/PhysRevE.91.031102},
journal = {Physical Review E},
number = 3,
volume = 91,
place = {United States},
year = 2015,
month = 3

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevE.91.031102

Citation Metrics:
Cited by: 6works
Citation information provided by
Web of Science

Save / Share:
  • The paper is devoted to experimental studies of formation of resonance cones in magnetized plasmas by pulsed RF source in the lower-hybrid (whistler) and the upper-hybrid frequency ranges. It is shown that in both frequency ranges, resonance cones exhibit similar dynamics after switching-on the RF source: at first, wide maxima of radiation are formed in non-resonance directions, which then become narrower, with their direction approaching the resonance one. While the resonance cones are being formed, one observes a fine structure in the form of secondary radiation maxima. It is shown that the characteristic formation time of stationary resonance cones ismore » determined by the minimal value of the group velocity of the quasi-electrostatic waves excited by the antenna. In the low-temperature plasma, this value is limited in the lower-hybrid frequency range by the spatial spectrum of the emitting antenna and in the upper-hybrid range, by the effects of spatial plasma dispersion.« less
  • In a Test Fusion Tokamak Reactor [R. J. Hawryluk et al., Phys. Plasmas 5, 1577 (1998)] experiment, the measured energy spectrum of the deeply trapped alpha particles is found to be 1 MeV too broad to be explained by classical collisions and the peak energy similarly off by 450 keV. The relativistic effect is proposed as an explanation. Here, we report high-resolution Monte Carlo (MC) and particle-in-cell (PIC) simulation studies in detail, under the assumption of a uniform magnetic field, for the identification of the cause of the observed anomaly. The 3.5 MeV alpha particles produced by thermonuclear fusion reactionmore » are broadened due to Doppler effect. The relativistic alpha particle dynamics are followed with the PIC code. The relativistic ion cyclotron instability grows to saturation on a time scale (10{sup -5} s) much shorter than the experimental time scale of 0.1 s. The MC code is then used to follow, in real time, the collisional slowing down of the gyrobroadened alphas, including the effect of the time delay in diagnostic pellet releasing and flight. Relativistic gyrobroadening is shown to be crucial in shaping the birth and slowed-down spectra. The resultant alpha particle energy spectrum fits well with that of the measurement, with a reduced chi square of unity.« less
  • The characteristics of obliquely propagating Dust Acoustic Waves (DAWs) in rotating and magnetized dusty plasma in the dayside tropical mesosphere are examined by incorporating adiabatic dust charge fluctuations. A Korteweg-de Vries equation is derived, which may support a nonlinear dust acoustic wave on a very slow time scale. The meteoritic dust in mesospheric plasmas on the dayside is charged positively due to photo- and thermionic emissions. The dynamics of the DAW with electronic, ionic, thermionic, and photoelectric currents along with obliqueness and effective gyrofrequency are studied. It is observed that the amplitude of the soliton depends directly on the obliquenessmore » {theta} and dust charge variation, respectively, while the width is modified inversely with these parameters. It is also observed that the effective gyrofrequency modifies the width inversely.« less
  • The present paper describes the numerical technique that has been developed, in the framework of the particle-in-cell (PIC) method, to study the dynamics of a nonneutral plasma along the magnetic field lines. In particular, the technique has been employed to simulate the formation and long-term evolution of large-amplitude electrostatic waves experimentally observed in electron plasmas confined in a Penning trap [W. Bertsche, J. Fajans, L. Friedland, Phys. Rev. Lett. 91 (2003) 265003]. Due to the peculiar features of the physical system, namely the existence of different time scales and the presence of a perturbative oscillating potential, ad hoc numerical techniquesmore » have been developed. In particular, with a suitable radial decomposition all important two-dimensional phenomena are fully taken into account while keeping the computational effort to that of a standard one-dimensional PIC codes. Moreover, a novel particle loading technique (ergodic loading) has been developed, which ensures a significant reduction of numerical noise. The results obtained with the present technique are in excellent agreement with the experiments [F. Peinetti, W. Bertsche, J. Fajans, J. Wurtele, L. Friedland, Phys. Plasmas 12 (2005) 062112]. Moreover, results presented here furnish clear evidences of the close relationship between the observed nonlinear structures and the Bernstein-Greene-Kruskal modes.« less