from Klenner et al. 2019
Comparison of the impact ionization process occurring in mass spectrometers in space (A) and in liquid beam laser desorption (B) for comparable energy impact and dispersion conditions. In A) ice grains hit a metal target and become partially ionized. In B) a pulsed infrared laser hits a water beam, which disperses and in turn creates ions and charged aggregates. In both cases the charged ions/aggregates are accelerated by a high voltage potential difference (neg./pos. HV) and detected after a characteristic (mass/charge dependent) time of flight. The lower panel (C) shows the main acceleration and drift zones within the CDA Chemical Analyzer mass spectrometer. Voltages are approximate and the regions are not to scale. Instrument recording may be triggered by charges exceeding thresholds on the target, acceleration grids or multiplier.