DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Characterization of hollow cathode plasma turbulence using coherent Thomson scattering

Journal Article · · Journal of Applied Physics
DOI: https://doi.org/10.1063/5.0071650 · OSTI ID:1978981
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3]
  1. Centre National de la Recherche Scientifique (CNRS), Orleans (France); Centre National de la Recherche Scientifique (CNRS), Orléans (France)
  2. Stanford University, CA (United States)
  3. Centre National de la Recherche Scientifique (CNRS), Orleans (France)

Turbulence in hollow cathodes used for space propulsion is believed to play an important role in anomalous electron transport and ion heating. In this work, the implementation of coherent Thomson scattering to identify and characterize MHz-frequency ion acoustic turbulence and kHz-frequency oscillations in the plume of a hollow cathode is achieved. In the presence of a background magnetic field of a Hall thruster, a number of unstable modes are observed. A directive ion acoustic mode propagating predominantly within a restricted angle around the magnetic field is found, exhibiting an energy scaling with wavenumber k of the form k-5.2±0.58, which differs from the classic Kadomtsev k-3 scaling for unmagnetized conditions. Bi-directional ion acoustic mode fluctuations propagating over a range of angles with respect to the magnetic field have been measured, possibly signifying the existence of a large-amplitude plasma wave, similar to the Buneman instability. Finally, electron density fluctuations in the kHz-frequency range, a possible consequence of drift-driven instabilities in the plane perpendicular to the magnetic field, have also been identified. Furthermore, these results not only are an indication of the diversity of wave types that exist in hollow cathode plumes but also point to the key role played by the presence of, and the configuration of, the magnetic field in their appearance.

Research Organization:
Stanford University, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Fusion Energy Sciences (FES); Air Force Office of Scientific Research (AFOSR)
Grant/Contract Number:
SC0020623
OSTI ID:
1978981
Journal Information:
Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 24 Vol. 130; ISSN 0021-8979
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English

References (67)

Ion acoustic turbulence and anomolous transport journal June 1985
Introduction to the interaction between energetic particles and Alfven eigenmodes in toroidal plasmas journal December 2018
Ion-acoustic turbulence and anomalous transport journal July 1988
Propulsion for CubeSats journal May 2017
Longitudinal waves in a perpendicular collisionless plasma shock: I. Cold ions journal December 1970
OGO 5 observations of electrostatic turbulence in bow shock magnetic structures journal July 1970
Measurement of the Electron Temperature by Thomson Scattering in Tokamak T3 journal November 1969
Study of stationary plasma thrusters using two-dimensional fully kinetic simulations journal January 2004
Landau Damping of Ion Acoustic Waves in a Uniform Magnetic Field journal January 1970
Nonlinear theory and angular spectrum of the ion-acoustic instability journal January 1973
Evidence of nonclassical plasma transport in hollow cathodes for electric propulsion journal March 2007
Potential fluctuations and energetic ion production in hollow cathode discharges journal October 2007
Dispersion relations of electron density fluctuations in a Hall thruster plasma, observed by collective light scattering journal March 2009
Compact lanthanum hexaboride hollow cathode journal August 2010
Low frequency oscillations in a stationary plasma thruster journal October 1998
Hall thruster plasma fluctuations identified as the E×B electron drift instability: Modeling and fitting on experimental data journal August 2013
Plasma oscillations in a 6-kW magnetically shielded Hall thruster journal May 2014
An axially propagating two-stream instability in the Hall thruster plasma journal July 2014
The importance of the cathode plume and its interactions with the ion beam in numerical simulations of Hall thrusters journal April 2016
Characteristics of an elongated plasma column produced by magnetically coupled hollow cathode plasma source journal March 2018
Scaling of spoke rotation frequency within a Penning discharge journal July 2018
Correlation of ion acoustic turbulence with self-organization in a low-temperature plasma journal August 2019
Anode geometry influence on LaB 6 cathode discharge characteristics journal November 2019
Self-organized standing waves generated by AC-driven electron cyclotron drift instabilities journal December 2019
Evolution of the ion−acoustic instability in a direct−current discharge plasma journal January 1975
Spectra of ion acoustic plasma instability journal January 1977
Coherent scattering of CO2 light from ion-acoustic waves journal January 1977
Anomalous electron transport equations for ion sound and related turbulent spectra journal January 1978
Study of density fluctuations in plasmas by small-angle CO2 laser scattering journal January 1980
Collective scattering of CO2-laser light from ion-acoustic turbulence journal January 1981
Observation of rotating magnetohydrodynamic modes in the plume of a high-current hollow cathode journal January 2021
Growth of the lower hybrid drift instability in the plume of a magnetically shielded Hall thruster journal May 2021
Plasma hollow cathodes journal August 2021
Weibel, Two-Stream, Filamentation, Oblique, Bell, Buneman...Which one Grows Faster? journal June 2009
Collisionless shock waves in plasmas journal October 1973
Measurements of microturbulence in tokamaks and comparisons with theories of turbulence and anomalous transport journal May 1985
Density Fluctuation Measurement by Far Infrared Light Scattering journal January 1982
Ion acoustic instability in collisionless shocks journal October 1972
An analysis of optical mixing in plasma scattering experiments journal September 1978
Electrostatic instabilities in current-carrying and counterstreaming plasmas journal January 1964
Scaling laws of density fluctuations at high- k on Tore Supra journal November 2004
Fluid theory and simulations of instabilities, turbulent transport and coherent structures in partially-magnetized plasmas of $\mathbf{E}\times \mathbf{B}$ discharges journal November 2016
Electron properties of an emissive cathode: analysis with incoherent thomson scattering, fluid simulations and Langmuir probe measurements journal July 2020
Numerical analysis of azimuthal rotating spokes in a crossed-field discharge plasma journal March 2018
Ion kinetics and nonlinear saturation of current-driven instabilities relevant to hollow cathode plasmas journal May 2019
Transient non-classical transport in the hollow cathode plume I: measurements of time-varying electron collision frequency journal October 2020
Transient non-classical transport in the hollow cathode plume II: evaluation of models for the anomalous collision frequency journal October 2020
The Rise of the Electric Age for Satellite Propulsion journal March 2017
C O 2 -laser scattering from thermal fluctuations in a plasma with two ion components journal March 1983
Cross-field electron diffusion due to the coupling of drift-driven microinstabilities journal August 2020
Ion acoustic turbulence in a 100-A LaB 6 hollow cathode journal December 2014
Propagation of ion acoustic wave energy in the plume of a high-current LaB 6 hollow cathode journal August 2017
Instability, Turbulence, and Conductivity in Current-Carrying Plasma journal July 1958
Rotating Spokes, Ionization Instability, and Electron Vortices in Partially Magnetized E × B Plasmas journal May 2020
Effect of Electron Trapping on the Ion-Wave Instability journal November 1969
Measurement of Spectrum of Turbulence Within a Collisionless Shock by Collective Scattering of Light journal August 1970
Anomalous Resistivity and Ion-Acoustic Turbulence journal November 1971
Study of the Current-Driven Ion-Acoustic Instability Using C O 2 -Laser Scattering journal March 1976
Spectrum of Small-Scale Density Fluctuations in Tokamaks journal June 1982
Wear Mechanisms in Electron Sources for Ion Propulsion, II: Discharge Hollow Cathode journal July 2008
Hall-Effect Thruster--Cathode Coupling, Part I: Efficiency Improvements from an Extended Outer Pole journal July 2011
Hall-Effect Thruster--Cathode Coupling, Part II: Ion Beam and Near-Field Plume journal July 2011
Electrical Facility Effects on Hall-Effect-Thruster Cathode Coupling: Discharge Oscillations and Facility Coupling journal July 2016
Rotational Waves in the Plume of an Externally-Mounted Hall Thruster Cathode journal December 2021
First-principles Modelling of the IAT-driven Anomalous Resistivity in Hollow Cathode Discharges I: Theory conference July 2016
First-principles modeling of the IAT-driven anomalous resistivity in hollow cathode discharges II: Numerical simulations and comparison with measurements conference July 2016
Spot-to-plume Mode Transition Investigations in the HERMeS Hollow Cathode Discharge Using Coupled 2-D Axisymmetric Plasma-Thermal Simulations conference July 2018