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Title: Plasma manipulation techniques for positron storage in a multicell trap

Abstract

New plasma manipulation techniques are described that are central to the development of a multicell Penning trap designed to increase positron storage by orders of magnitude (e.g., to particle numbers N{>=}10{sup 12}). The experiments are done using test electron plasmas. A technique is described to move plasmas across the confining magnetic field and to deposit them at specific radial and azimuthal positions. Techniques to fill and operate two in-line plasma cells simultaneously, and the use of 1 kV confinement potentials are demonstrated. These experiments establish the capabilities to create, confine, and manipulate plasmas with the parameters required for a multicell trap; namely, particle numbers >10{sup 10} in a single cell with plasma temperature {<=}0.2 eV for plasma lengths {approx}10 cm and radii {<=}0.2 cm. The updated design of a multicell positron trap for 10{sup 12} particles is described.

Authors:
; ;  [1]
  1. Department of Physics, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0319 (United States)
Publication Date:
OSTI Identifier:
20860464
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 13; Journal Issue: 12; Other Information: DOI: 10.1063/1.2390690; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 43 PARTICLE ACCELERATORS; DESIGN; ELECTRON TEMPERATURE; ELECTRONS; EV RANGE; ION TEMPERATURE; MAGNETIC FIELDS; PLASMA; PLASMA CELLS; PLASMA CONFINEMENT; PLASMA POTENTIAL; POSITRON SOURCES; POSITRONS; TRAPS

Citation Formats

Danielson, J. R., Weber, T. R., and Surko, C. M.. Plasma manipulation techniques for positron storage in a multicell trap. United States: N. p., 2006. Web. doi:10.1063/1.2390690.
Danielson, J. R., Weber, T. R., & Surko, C. M.. Plasma manipulation techniques for positron storage in a multicell trap. United States. doi:10.1063/1.2390690.
Danielson, J. R., Weber, T. R., and Surko, C. M.. Fri . "Plasma manipulation techniques for positron storage in a multicell trap". United States. doi:10.1063/1.2390690.
@article{osti_20860464,
title = {Plasma manipulation techniques for positron storage in a multicell trap},
author = {Danielson, J. R. and Weber, T. R. and Surko, C. M.},
abstractNote = {New plasma manipulation techniques are described that are central to the development of a multicell Penning trap designed to increase positron storage by orders of magnitude (e.g., to particle numbers N{>=}10{sup 12}). The experiments are done using test electron plasmas. A technique is described to move plasmas across the confining magnetic field and to deposit them at specific radial and azimuthal positions. Techniques to fill and operate two in-line plasma cells simultaneously, and the use of 1 kV confinement potentials are demonstrated. These experiments establish the capabilities to create, confine, and manipulate plasmas with the parameters required for a multicell trap; namely, particle numbers >10{sup 10} in a single cell with plasma temperature {<=}0.2 eV for plasma lengths {approx}10 cm and radii {<=}0.2 cm. The updated design of a multicell positron trap for 10{sup 12} particles is described.},
doi = {10.1063/1.2390690},
journal = {Physics of Plasmas},
number = 12,
volume = 13,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
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  • Much of the analysis of instabilities and wave propagatin in warm plasma involves perturbation solutions of the Vlasov or collisionless Boltzmann equation. In general, a dielectric tensor which describes the response of the plasma to perturbations must be derived. A typical derivation involves choosing an equilibrium distribution function which models some plasma of interest, calculating a perturbed distribution function by solving a partial differential equation (usually by the method of characteristics), calculating density and current moments of this perturbed function, and using these quantities in Maxwell's equations. For many equilibrium models of physical interest, this process can be completely carriedmore » out analytically. However, even in simple cases, the procedure is tedious-involving hundreds or thousands of separate algebraic or calculus operations and is fraught with opportunity for error. It will be illustrated here how the symbolic manipulation language MACSYMA can be used to automate energy many of the steps involved in such derivations. By way of example, the classic problem of oscillation in a homogeneous, uniformly magnetized plasma will be considered.« less