Internal physics of the ion-sensitive probe

Abstract Due to its usefulness as a diagnostic for high-density magnetized plasmas, a complete picture of particle motion and potential surfaces within the Ion-Sensitive Probe (ISP) is desired. To that end, results from an ISP with a segmented collector are presented. Asymmetry in the electron current to the collector is found to be in the ExB drift direction, consistent with previous numerical studies of the probe. Asymmetry in the ion current is found to be due to geometric “shadowing” of parts of the collector surface. Additionally, insight into the ion velocity distribution function (IVDF) is gained by comparing Ti,⊥ to the thermal energy required for an ion to overcome the potential barrier inside the probe.