Rotating field confinement of pure electron plasmas using trivelpiece-gould modes

A "rotating wall" electric field is shown to give steady-state confinement of a column of 3 x 10(9) electrons in a Penning-Malmberg trap at 4 tesla. By increasing the frequency of the rotating drive, a central-density compression by a factor of 20 has been obtained. For both dipole and quadrupole drives (i.e., m(theta) = 1 and 2), the compression rate depends on drive frequency, exhibiting peaks associated with k(z) not equal 0 Trivelpiece-Gould plasma modes. The drive also causes plasma heating, but cyclotron radiation cooling keeps the temperature low enough that background gas ionization is negligible. [S0031-9007(98)07771-0].