Lifetime scaling in non-neutral plasmas

摘要

The non-neutral plasma community has long believed that the lifetime of plasmas held in Penning-Malmberg traps scales as #tau#_m propor.to B~2/L~2. The lifetime, #tau#_m is the time for the plasma’s central density to decrease by two, B is the trap250L痵 axial magnetic field, and L is the plasma length. However, the case for this scaling law is weak. Other scaling laws work just as well. In particular, #tau#_m propor.to B~2/L~3 is in equally good agreement with lifetime measurements. This scaling would result from transport induced by quadrupolar magnetic field errors.