plasma, normal modes, mode frequencies, Penning trap, oblate charge, eigenfunctions
A numerical method is presented for finding the eigenfunctions (normal modes) and mode frequencies of azimuthally symmetric non-neutral plasmas confined in a Penning trap whose axial thickness is much smaller than their radial size. The plasma may be approximated as a charged disk in this limit; the normal modes and frequencies can be found if the surface charge density profile sigma(r) of the disk and the trap bounce frequency profile wz(r) are known. The dependence of the eigenfunctions and equilibrium plasma shapes on nonideal components of the confining Penning trap fields is discussed. The results of the calculation are compared with the experimental data of Weimer et al. [Phys. Rev. A 49, 3842 (1994)] and it is shown that the plasma in this experiment was probably hollow and had mode displacement functions that were concentrated near the center of the plasma.
Original Publication Citation
Jenkins, Thomas G. and Ross L. Spencer. "Vibrational modes of thin oblate clouds of charge." Physics of Plasmas 9 (22): 2896-298.
BYU ScholarsArchive Citation
Jenkins, Thomas G. and Spencer, Ross L., "Vibrational modes of thin oblate clouds of charge" (2002). All Faculty Publications. 537.
Physical and Mathematical Sciences
Physics and Astronomy
© 2002 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Physics of Plasmas and may be found at http://link.aip.org/link/?PHPAEN/9/2896/1
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