heating target for RFQ tests. Now the wiring is insulated with alumina beats and tubing and the target has the standard Ta alkali element mixture

Unfortunately I deleted some entries, so here a short summary in combination with a screenshot of the striptool

heated to 580A, vacuum increased over time from 4.8 to 5.6E-7T

HV up to 30kV - current of 37 uA - seems fine

Mass scan not possible, ops found a water leak in the magnet PS, optics around the magnet are thereofre also not available and red in EPICS

NOTE: all FC values are in reversed bias!!

source +4.5V, 2nd Rep 0V:  RFQ offs =0V, RFQ Ampl = 20V, 1 MHz (current 0.26A), locked up

 about 2E-9A at FC0

one spark observed

source -5.5V, 2nd Rep 0V:  RFQ offs =0V, RFQ Ampl = 20V, 1 MHz (current 0.26A), locked up

  about 4E-11A at FC0

source -12V, 2nd Rep 0V:  RFQ offs =0V, RFQ Ampl = 20V, 1 MHz (current 0.26A), locked up

  about 5E-11A at FC0

  two sparks observed

source +4.5V, 2nd Rep 0V:  RFQ offs =0V, RFQ Ampl = 20V, 1 MHz (current 0.26A), locked up

  about 3E-10A at FC0

source -5.5V, 2nd Rep 0V:  RFQ offs =0V, RFQ Ampl = 20V, 1 MHz (current 0.26A), locked up - done again since not sure if the restore of the tune was done properly for this

  about 4E-11A at FC0

done, source +4.5V, 2nd Rep +12V:  RFQ offs =0V, RFQ Ampl = 20V, 1 MHz (current 0.26A), locked up

   about 3E-10A at FC0

 1 spark during HV ramping

done, source +4.5V, 2nd Rep&exit +12V:  RFQ offs =+12V, RFQ Ampl = 20V, 1 MHz (current 0.26A), locked up

there is something visible <~ 2E-12A at FC0

reduced current to 550A and leave it over night.

Short summary:

suppression possible but RFQ has to be shifted, the "only source shift" mode yielded a worse suppression than expected - unfortunately no mass scans have been possible, which would help to get some information on possible effects