skip to main content


This content will become publicly available on May 8, 2019

Title: Detection of an electron beam in a high density plasma via an electrostatic probe

Here, an electron beam is detected by a 1D floating potential probe array in a relatively high density (10 12–10 13 cm -3) and low temperature (~5 eV) plasma of the Magnetic Reconnection Experiment. Clear perturbations in the floating potential profile by the electron beam are observed. Based on the floating potential profile and a current balance equation to the probe array tips, the effective width of the electron beam is determined, from which we determine the radial and toroidal beam current density profiles. After the profile of the electron beam is specified from the measured beam current, we demonstrate the consistency of the current balance equation and the location of the perturbation is also in agreement with field line mapping. No significant broadening of the electron beam is observed after the beam propagates for tens of centimeters through the high density plasma. These results prove that the field line mapping is, in principle, possible in high density plasmas.
 [1] ; ORCiD logo [2] ;  [2] ;  [2]
  1. Rensselaer Polytechnic Inst., Troy, NY (United States)
  2. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Plasma Physics and Controlled Fusion
Additional Journal Information:
Journal Volume: 60; Journal Issue: 7; Journal ID: ISSN 0741-3335
IOP Science
Research Org:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Sponsoring Org:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
Country of Publication:
United States
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; Electron beam detection; floating potential; fi eld line mapping
OSTI Identifier: