AFP Plans for LS 2 Michael Rijssenbeek LS

AFP Plans for LS 2 Michael Rijssenbeek Ø LS 2 Plans 2016 2017 SD DPEjj CEPjj γγ→ W, Z, γ XRP Far – 218 m TCL 6 31 MAY 2018 XRP Near – 206 m Patch. Panel – 212 m Q 5 AFP@LS 2 1

AFP Plans for LS 2 Boundary condition: • Keep the existing XRPs and controls AFP Maintenance/Upgrade Tasks: • • Stations: springs/clean screws ? Spring-driven extraction (while reaching the HOME switch), doesn’t reach OUT Si. T Holder and heat exchanger • Refurbish 3 D Si pixel detectors: replace all rad-damaged sensors – Upgrade the heat exchangers (Al foam heat exchanger) – Keep current pixel type until new 25× 125μm 2 sensor and FE chip is available (2022 ? ). Question: do we have enough ‘old’ sensors and FE-I 4 s ? • Refurbish To. F • • • DAQ: VLDB/COB/RCE/ATCA, and radhard transceivers … DCS: regular upgrades Infrastructure: only modest changes (cooling, …) 31 MAY 2018 – New glue-less LQbars; new MCP-PMTs. (LGAD will not be ready yet …) – New To. F signal feedthroughs – LED pulser? (Q fiber feedthrough? ) – New To. F Electronics: pico. TDC, CFD, Trigger? AFP@LS 2 2

Pots not reaching HOME (3 May 2018) Two weeks ago one of the AFP RP did not reach the HOME position during a test for spring-driven emergency extraction (for instances when a beam dump or beam instabilities would occur). It seems that the pots are not extracted as fully as in the past during spring-driven extractions. This may be due to aging of the springs [1, 2], aging of the radhard grease of the linear motor screw, effects of cabling, or a combination of these. We are studying a reliable fix to this potential problem, for implementation during TS 1. This intervention would most likely require a new BBA alignment even in the case To. F is not installed. We think an intervention will be necessary since if this happens during LHC operation, the LHC Beam Injection Permit will be blocked until the pots can be driven to HOME by intervention of the AFP On. Call or ultimately by motor-controller expert (Sylvain Ravat). Then, the pots might have to be set in "holyday mode" (i. e. will be unable to be inserted until the problem is fixed). For now, we propose to monitor the problem, i. e. we want to track the pot position in HOME and the margin available beyond the HOME position itself, especially after an emergency extraction, in order to ensure that the problem does not deteriorate further. We hope to have a monitoring in place very soon. If the problem deteriorates significantly, we must decide to go to Holiday Mode. During TS 1 we intend to solve the problem by 1) adding a spring of the appropriate spring constant in parallel to the existing spring, 2) or add a gravitational weight plus pulley, 3) reconfigure cabling, and 4) testing the spring-driven extraction to ensure better operation. [1] DAI 6228276, ALCOMEX Resorts TR 2380: d=4 mm, OD=24 mm, L 0=196 mm, Lmax=L 0+102 mm, k=3. 92 N/mm, Fmax=470 N, F 0=70 N www. sarlimpexcom. fr/ [2] Springs are mounted at 250 mm length, i. e. are under F=F 0+(250196)*3. 92=280 N pre-tension each 29 MAY 2018 Figure 3. The IN, OUT, and HOME switches and their ideal ranges settings. In addition the electrical STOP needle switch (and photo insert) is shown and its relation to the positions of the other switches. AFP TM 3

Resolver Positions after Spring-Driven Extraction • • Maciej 03. 05. 2018 Time Axis: • NO clear deterioration seen, except possibly in A-Far – – – • 1. 6. 2017 – 3. 5. 2018 OUT was not reached in almost all cases … some strange outliers … MPP presentation 29 MAY 2018 AFP TM 4

Must add extra force at End of Extraction Need ~2 -3 mm extra displacement: 3 mm× 4 springs× 3. 9 N/spring/mm = 45 N 1. put 2 extra springs in parallel, e. g. TR 1210 L 0=90+50 mm, Lmax=308 mm, Fmax(Δx=160 mm)=35 N F(Δx=250 -140=110 mm)= 27 N/spring • disadvantage: extra strain on motor • mounting exerts strain on station BBA – BBA for Far stations is required anyway … – ordered springs … (MR) 2. put 4. 5 kg weight over pulley • fixed force only • no mounting strain on station: hook and hang weight … • but: must design/build pulley 3. Touching the Station (not LVDT/ switches/motor/controls) Requires BBA and Loss Maps … • 29 MAY 2018 Revisit this issue in LS 2 ! AFP TM 5

Draft AFP LS 2 Schedule • January 2019: extract all detector packages Clean room / radiation area. Flange–off pots … • 2019 – 2020: – LSS 1: RP stations maintenance: clean linear screw? switches? (10 days, no particular time frame) – LSS 1: movement tests (1 week) – LSS 1: cooling upgrade (remotely controlled valves) (1 week) – LSS 1 -USA 15: shorten Fast Trigger cable by ~10 ns (? ) (5 days, if deemed possible) – Cleanroom/radiation area: refurbish Si. T detectors (new detectors), cooling – Cleanroom/radiation area: refurbish To. F: • glueless LQbars; new MCP-PMTs(? ); LED pulser; new signal feedthroughs; … – General Lab: VLDB and TDAQ setup testing – General Lab: pico. TDC testing in lab – Si. T/To. F beam tests (where? ) • Early 2021 (or Late 2020): 31 MAY 2018 – LSS 1: install and commission TDAQ in LSS 1 (3 weeks) – LSS 1: install detector packages (1 week + 2 weeks spare) – LSS 1: survey, re-calibrate (1 week) – LSS 1: commission detectors Si. T and To. F (6 weeks intermittent access) AFP@LS 2 6

Engineering Change Request (ECR) • As for other shut-downs, an ECR will be prepared that specifies details of the work in the LHC and possible interference/impact on other systems and services: – Currently NOT Foreseen: • • NO opening of beam pipe (e. g. for Pot removal) NO cabling campaign (but: study/work to shorten the Air. Core cables by ~10 ns) • Survey, movement calibration (EN-SMM-ASG) • • • Transport (shielding blocks) RP for activation classification and transport (work/dose planning) Compressed Air – install remotely controlled valves – Currently Foreseen: – survey requires line-of-sight from AFP to Q 6 temporary (? ) removal of top shielding blocks after TCL 6 • ECR LHC-XAFP-EC-0005 “Maintenance of the AFP Detectors over LS 2”, will be ready for review in possibly June(? ) – also specify work on surface … • Possibly, there will be a common ECR for all ATLAS Roman Pots (AFP & ALFA) ? 31 MAY 2018 AFP@LS 2 7

LHC-XAFP-EC-0005 • Draft in preparation 31 MAY 2018 AFP@LS 2 8

Back-up Slides 31 MAY 2018 AFP@LS 2 9

Manpower Issues – AFP Perspective • Sune leaves ATLAS: limited availability, only ALFA. (Sune is/was RC for all FWD) • Grzegorz Gach (Soft/Sim, DP/DQ for ALFA/AFP) leaves AGH-UST in mid-June • Kris has limited time • Impact for 2018: – need a RC for 2018 (Maciej, MR – end-May? AFP On-Call) – need a contact for MPP and Collimator group, LHC Operations, … (MR from end-May onwards? ) • area where Sune will be most sorely missed by AFP – need a new convener and expert for Soft/Sim starting NOW – must train the new person … (? ) • Long-term impact: – Must find a common RC/TC position for Roman Pots during LS 2 and Run 3 • • • maintenance/repair/upgrade of ALFA and AFP learn from Sune, Maciej, MR, … identify person inside/outside AFP/ALFA …? • AGH-UST Cracow: Krzysztof Janas (Postdoc Leszek)? Krzysztof Ciesla? Antonello S. ? – Must attract more soft/sim people 31 MAY 2018 AFP@LS 2 10

Lab Space for AFP over LS 2 • 2 types of Lab spaces are urgently needed: – clean room & radiation area (25 m 2) for detector refurbishment, irradiated electronics repair, storage … (risk assessment for Rad work; in ECR? ) – general lab space (50 m 2) for TDAQ, spare station tests, parts storage, … • prefer both spaces to be near the Point 1 – US 15 area ! 31 MAY 2018 AFP@LS 2 11