SDR, EVC, and SDREVC: Limitations and Extensions

Methods for reducing the radius, temperature and space charge of a non-neutral plasma are usually reported for conditions which approximate an ideal Penning Malmberg trap. Here, we show that (i) similar methods are still effective under surprisingly adverse circumstances: we perform strong drive regime (SDR) compression and SDREVC in a strong magnetic mirror field using only 3 out of 4 rotating wall petals. In addition, we demonstrate (ii) an alternative to SDREVC, using e-kick instead of evaporative cooling (EVC) and (iii) an upper limit for how much plasma can be cooled to T < 20 K using EVC. This limit depends on the space charge, not on the number of particles or the plasma density.

Automated summary

In this study, we investigate methods for reducing the radius, temperature, and space charge of a non-neutral plasma under adverse conditions. Our findings show that the strong drive regime (SDR) compression and SDREVC methods are still effective even when using only 3 out of 4 rotating wall petals in a strong magnetic mirror field. We also propose an alternative method to SDREVC by using e-kick instead of evaporative cooling (EVC), and determine an upper limit for how much plasma can be cooled to T < 20 K using EVC, which depends on the space charge rather than the number of particles or plasma density.