Operation of an E ∥ B end‐loss ion spectrometer on the Tara tandem mirror

An E ∥ B end‐loss ion spectrometer from the Livermore TMX‐U tandem mirror experiment was installed on Tara for high‐resolution ion spectroscopy. This diagnostic contains parallel electric and magnetic fields, separating the masses and energies of the ions over 128 collector plates. The ion energy distribution nominally yields confining potentials and parallel ion temperatures. Additional experiments have diagnosed the resonance position of the central cell ion cyclotron heating, rf enhanced losses of high‐energy sloshing ions in the axicell (‘‘plug’’), and observation of MHD instabilities at higher time resolution (20 kHz).