Megagauss Fields by Automodulating Currents

  • V. Nardi


The magnetic field building-up is related with the filamentation of current channels which is typical of dense plasmas in a variety of experimental conditions. Specifically a sequence of different typical stages is considered for the filamentary current sheath of a coaxial accelerator (plasma focus) in each of which the plasma is in a quasi-stationary state. A description of plasma and field fine structure is given in term of phase-space particle density and electric and vector potentials. The break-up of the filamentary structure generates three-dimensional current loops in the plasma with local amperian currents which can be higher than the accelerator total current. These loops have toroidal and poloidal fields with a maximum of amperian current on the loop axis in the region of poloidal-field peak intensity. Mirror effect on this region creates a steep potential wall with some interruption of the current carrier flow.

Extreme values of current and magnetic field (up to ~108G) are due to the high-energy particles which are produced by the potential wall as in an electronic ram. The time for potential wall and magnetic field building-up is compressed by radiative energy losses for an increasing plasma transparency when the electron cyclotronfrequency reaches the plasma frequency and negative-temperature conditions are created.


Plasma Focus Plasma Column Axial Channel Mirror Effect Virtual Cathode 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Plenum Press, New York 1976

Authors and Affiliations

  • V. Nardi
    • 1
    • 2
  1. 1.Istituto Elettrotecnico Nazionale Galileo FerrarisTorinoItaly
  2. 2.Stevens Institute of TechnologyHobokenUSA

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