Time-of-flight analyzer for ion end loss of a mirror plasma

A time-of-flight analyzer has successfully been used to measure the extracted charge-state distribution and impurity level of an ECRH mirror plasma. End-loss temperatures for each ion species have been determined from the rise time of the analyzer output pulses. Ions entering the line-of-sight device are first accelerated by a two-aperture lens and are then focused with an einzel lens. Electrostatic deflection plates chop the ion beam into short pulses which travel down a 1.20-m tube to an electron multiplier. Ion spectra are typically summed at a rate of 1 kHz using a hardware signal averager.