The Trom Space Plasma Experiment TroSPEx shild Fredriksen Dep' Physics, Univ' Troms, N9037 Troms, No

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The Tromø Space Plasma Experiment
(TroSPEx)Åshild FredriksenDep. Physics, Univ.
Tromsø, N-9037 Tromsø, Norway
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Abstract

• The plasma laboratory at the University of
  Tromsø is being modernized and reoriented towards
  space related plasma experiments. To facilitate
  this, we are assembling a device based on a DP-
  machine, with an additional helicon source. The
  main purpose is to perform studies of
  acceleration processes such as double layers, and
  of waves and turbulence in flowing plasmas.. With
  this device, ion or electron beams can be
  produced by biasing the anode chamber at one end
  of the plasma with respect to the main chamber,
  or a current-free outflowing plasma can be
  produced by the helicon source in the other end.
  The plasma produced will be weakly magnetized,
  and we will have the possibility to study plasmas
  with two different (up to four) ion species.
  Plasma diagnostics will be performed by a variety
  of probe techniques as well as mass and energy
  spectrometry (Hiden EQP) already available. The
  bulk of data digitizing will be based on PCI
  cards from National Instruments with Labview
  programmed user interface. Motor probe control
  will be performed through the same interface.
• Acknowledgement This project is made possible
  by a 1.4 Mkr grant from the University of Tromsø.

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The existing chamber
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Filaments on walls
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Anode part of chamber
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The double plasma chamber with external helicon
source and internal DC discharge and anode
chamber
Anode chamber part
Helicon source
Match box
RF ampl
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Examples of possible on-axis magnetic fields
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Diagnostics

• Probe diagnostics
• Swept Langmuir diagnostics
• Swept and fixed biased emissive probes
• Triple probes
• Ion energy analyzers (retarding field)
• Hiden EQP mass and energy analyzer
• Mach probes
• Digitizers and controllers
• 2x4 channels, 4 MHz, 12 bits National Instruments
  PC-card
• 1 GHz bandwidth digital oscilloscope
• 16 ch 256 kHz AD/DA NI cards
• 2 1D motor probes, 1 2D motor probe

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Main topics

• Studies of instabilities and heating in plasma
• flows and beams.
• Acceleration and instabilities in current-free
  expanding plasmas
• Interactions between spatially defined ion beams
  onto thermal background plasma.
• Instabilities in beams with two ion species
• Counterstreaming beams.
• Wave heating of ions

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Traditional DP plasma beam setup
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Expanding plasma setup
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Ion beam into counterflowing plasma