List of GTS Ghost Beam Experiments - 3/11/19

1. Measuring Ions
   • Purpose: Determining whether trapped ions are present in the accelerator after an electron beam run.
   • Experiment Details:
   1. Run 100-500uA electron beam for a fixed amount of time with GHV=100kV, GS=150A and anode biased at 1kV...enough to produce a visible ghost beam on viewer 2.
   2. Turn off real electron beam
   3. With the GHV and GS on, turn anode bias down to zero - if ions are trapped between the anode and GS, they will move towards the cathode.
   4. Measure current on cathode via an ammeter. If this is not possible, then we can measure current on the anode via an ammeter.
   • Null Hypothesis No current reading on cathode/anode, implying there are no trapped ions between the cathode/anode.
   • Duration of Experiment 1-2 hours
   • Setup/Equipment Needed Need to be able to measure current on either cathode or anode - perhaps we can connect an ammeter in series with either the cathode or anode?

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