Preliminary minutes of the TREX 04-03-22

1. ECR for ZDC cabling installation for Run 3

• Francisco mentioned request/information from J.P. Corso for the cable integration (... Francisco please complete).
• Presentation given by Sorina Popescu (ECR 2711613; LHC-X5ZDC-EC-0004).
• Motivation for the change is to minimize radiation damage of the optical fibers, provide better grounding for the electronics and services and meet physics objectives (please see the ECR).
• Content of the work is relocation of the equipment from LHC tunnel to UJ 53-57 bunkers. New routing for signal and HV cables is needed.
• Time schedule - installation to be performed before the ion run 2022 -> TS1+TS2.

Discussion:

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Q-FSG - Is there a request for a new AUG within the bunker?

A-SP - No, there is no need for this.

A-WZ - To be checked with HSE if it is fine in terms of the safety with respect to the HV installation (question to be addressed).

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Q-PF - Concerning Run 4 integration. Recalling that all the cables needs to be removed for HL-LHC activities and reinstalled after

A-SP OK for the ZDC team.

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Q-JW-  Opening of the sealing or using existing duct? To pull the cables is the scaffolding needed on the side of cryo-line (cryo will be operational)? Are the cables sufficiently RadHard?

A-SP - Existing duct will be used, no extra opening in the wall.

A-PBB - work behind the beamline is needed. Exceptional authorization.

A-WZ - destructive work (drilling was already done). Installation of the mini-racks can be still done in advance.

A-SP - cables are supposed to be RadHard (CMS expert confirmed).

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Q-JS - In case of over BP activities TE-VSC should be informed about the activity to avoid work at the sensitive environment  + vacuum valves must stay closed during the intervention.

A- PBB - VSC will be informed for purpose of the VIC.

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Q- MBM - routing is supposed to go behind the TAN, is this fine during the TS after p-p run (potential RP issue)?

 A- PBB - 1day for pulling  + extra time for connectors;

Comment-MM - Installation of the fibers in the bunker is irreversible in terms of ZDC operations. Once this is done we need to go ahead.

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Q-WZ - Radiation cables - what is going to be used for the installation and how is it within the baseline of the LHC?

A- PBB - standard solution for radiation areas will be used (to be confirmed).

A-PF only tempo solution, there is this HL-LHC RadHard cables strategy (previous TREX).

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FSG - OK for the LMC approval.

2. Space management at the UJ bunker for Run 3 & 4

• Presentation given by Francisco Sanchez Galan.
• Recall on the space management purpose, access etc.
• Bunkers used for storage BRAN & ZDC.
• There will be new sarco after LS3 - compatibility with the logistics to be checked.
• Need for active space management?

Discussion:

Comment - SP - bunkers exclusively build for purpose of the experiments (sarco storage).

Comment - MM - CMS sarco to be declared as waste. 

General discussion - How to indicate occupancy of the bunker for the access (can be done easily via INFOR?)

Comment - MM - it will be great is the TREX can initiate the discussion with RP and experiments for waste management.

3. AOB

No AOB addressed.

Minutes written by JS - 04-03-2022