TAX interlock requirements & usage in IH

Wednesday 14 Jun 2023, 11:30 → 13:00 Europe/Zurich

864/2-B29 - SY-STI Visitors Room (CERN)

Points to discuss:

Discuss together what XTAX in TCC2 need to be used as beam dump & EIS equipment in the post-LS3 (eventually High intensity) era, as well as what operational and interlocking conditions can and/or need to be set. This is crucial to be able to define the scope of each TCC2 TAX upgrade for NA-CONS /HI ECN3.

The goal of the meeting is to clarify and produce a clear list of all the operational conditions of each of the TCC2 TAX. Properly identify what type of usage is e.g., standard shared operation, EIS, accident scenario, etc etc. And eventually define any follow-up actions. 

Presence:

SY-STI: Rui Franqueira Ximenes;

BE-EA: Miguel Lino Diogo Dos Santos, Johannes Bernhard; 

SY-ABT: Matthew Alexander Fraser;

BE-OP: Kevin Shing Bruce Li;

TE-MPE: Antoine Colinet, Ivan Romera Ramirez

NOTES & ACTIONS

Operation

• High Intensity shall be considered only on dedicated delivery to the ECN3 experiment.
• Shared/SFTPRO cycle in the North Area will be at todays' current intensities -> max 1.5e13
• Not decided & not baseline, but if is decided that TAX absorbers in T2 and T6 need to be replaced anyway, it may allow 2 new experiment (Na64 in T2 w/ electron beams and Muon-e in T6) which may request higher intensity in these lines (2e13 ?)
  • ACTION Johannes/Miguel -> state these in the specs

Interlocking

• Dedicated cycle will have specific limits on interlocking, to be implemented on the operation side via the BIC e.g. extraction not possible if T4-P42 TAX is in an out of given hole position (Implementation as it is done in the LHC TEDs). Matrix with conditions shall include TED TT20. Likely having a TT20-TAX beam flag, with an underlying intensity limit (likely SMP(?) at 1.5e13ppp)
• When alternating Dedicated and Shared beams in the NA, TAXP42 will a priori not be moving up and down. But if ECN3 is accessed, then behaviour shall be as of today, with TAXP42 moving into beam stopper position (EIS-f for ECN3 access). This would have to inhibit dedicated cycle injection. With TAX in a hole position, P42 Dump is to be considered beam stopper in case of access to ECN3 ?
  • ACTION Rui -> Check with BE/ASR & EN/AA . 
• Experiments in ECN3 (downstream TAX) will also have their own beam interlock requirements

Accident scenarios. - What happens if few shots hit the TAX?

• Provided one TAX table is enough as a beam-stopper/ dump, then second table can serve as 2nd redundant equipment in case first one fails with an accident. E.g. Currently H2, H4 and H8 are only moved 1 table during access. In P42 TAX this does not happen due to higher intensity and thus interest in having more interaction lengths. Downstream table may then need to have identical material configuration as the upstream one. 
  • ACTION Rui -> Check with BE/ASR & EN/AA the idea. 
• Alternatively (plan b), one could make the P42 dump as a redundant beam stopper. Either by moving it (like a beam stopper), but that would be technically complicated given its large size and the fact it may be radioactive (if TIDVG4 hot spent device is used), or with a set of bumpers upstream and downstream.
  • ACTION Johannes -> & Matt to check the bumper case
  • ACTION STI -> Check if the TIDVG4 could be used as BS. 
  • ACTION Matt -> Provide beam spec (size) at the P42 dump location. 
• One other technically possible accident scenario is extracting quickly (~20ms) due to resonance (?) on the bumpers in LSS2. Could be detected via fast running sums of the BLM or via the dI/dt on the BCTs. Shall be added to the specs (even if likelihood is low). 
  • ACTION Johannes/Miguel -> add this scenario to specs
  • ACTION Kevin -> Organize some MD tests on this ?