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7	7	This electron current is measured as a function of time. By matching the corresponding signal within the timing of one rotation you can measure the electron current induced when the wire scans vertically and horizontally. The magnitude of the electron current is prortional to the magnitude of the beam current, hence giving us our vertical and horizonal profiles.
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9	10	The BPMs are used to monitor the position of the beams and also to measure the overlap of the ion beam with the neutral beam.
10	11	This is done by blocking the ion beam upstream at the chopper electrostatic lens. With the laser on, the laser induced neutral beam passes through the chopper field and the beam profile can be measured. Then the laser is turned off and the chopper is grounded. This allows the ion beam with out laser induced neutrals to pass through. The ion beam profile is then measured and the overlap can be determined.