ThermalBreakin

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Note: these instructions may change as we learn from the target operation.

DO NOT EXCEED 100 uA on Ca-48 target without explicit instructions from the RC until further notice!

Added: should be done with a 6x6 raster

1. Set SAM and quartz HVs for integration mode
2. Start with Ca-40 target at 50uA
3. Take data for 1 hour, carefully monitoring:
   • asymmetry widths
   • collimator temperatures (expect ~ W at 50uA)
   • cold ladder temperatures
   • Post screen captures to the logbook
   • Note anything out of the ordinary
   • Don't hesitate to call RC for guidance!
4. If everything seems steady, go to 100 uA on Ca-40
   • Follow steps from 2 above
5. If everything seems steady, go to 150 uA on Ca-40
   • Follow steps from 2 above
   • Note: they might not be able to deliver 150 uA, so just run at the highest available current up to 150uA
6. Assuming that everything went well with the Ca-40 target, continue with following steps
7. Move to the Ca-48 target and ask for 50 uA
8. Take data for 1 hour, carefully monitoring:
   • asymmetry widths
   • collimator temperatures (expect ~330 W at 50uA)
   • cold ladder temperatures
9. If everything seems steady, go to 100 uA on Ca-48
   • Follow steps from 8 above
   • Note: they might not be able to deliver even 100 uA, so just run at the highest available current up to 100uA

Explanation: The calcium oxidizes very quickly, and the presence of oil residue or an oxide layer could affect the thermal contact/conductivity so we want to carefully ablate the surface layer and make sure that we have stable target conditions to avoid damaging it with high current.