AMS tracker hardware status (mechanics and cabling)

1. AMS tracker hardware status(mechanics and cabling) • off-line operations • preparation for integration University of Geneva staff involved: Université de Genève Florian Masciocchi Philippe Bouvier Javier Mesa Maarten Weber Manfred Willenbrock* Franck Cadoux Eric Perrin* Divic Rapin * Retirement approaching With the help of S.Lucidi (Perugia) for paper work (QA) NIKHEF and NLR staff involved: Bart Verlaat, Erno …, Johannes Van Es, Aswin Pauw Divic RAPIN, UniGe AMS splinter tracker , Septidi 7 Brumaire 217 (october 28, 2008)

2. Ladder repair (test with mobile station) • Non working ladders were: • L15AP098 (read-out:600 oct:8 pwg:1 TDR:1B) Layer:8, slot:7M (---) bad K cable  recoverable  repairing of cable failed Spare S-type cable was used • L12AJ019 (read-out:309 oct:3 pwg:1 TDR:3B) Layer:4, slot:6P (+-+) K cable disconnected  recoverable with front shell opening

3. K flight cable connector of L15AP098 DR. july 18, 2008 1.5 ohm 6 ohm Line 5 (H1) Pin 7 (H1) Apparent repairing by resoldering pin 7, but failure showed again after reinstalling sleeve  Change cable (s-type) 1.5 ohm Pin 2 Guard ring • Test of K flight cable showed interruption on pin 7 of connector of TDR side. • Surgery to access connections on patch panel for better diagnostic. • Contact was re-established (by chance). Poor contact through the Airborne connector. • Airborne connector faulty ?? Or cold soldering ??? • This problem occurred already with another cable.

4. Ladder L12AJ019 Layer:4 Col:6P (+X –Y +Z) octant:3 pwgrp:1 TDR:3B Read-out: 309 ? Pictures taken may 8, 2007. After tests. Just before closing last shell DSCN0356.JPG DSCN0353.JPG Connection hidden during most of the time by supporting bars. Tests were OK

5. Fixation of connectors with Kapton tape Access by outer side only ! U OK

6. Front shells were opened Special tools were designed to hold the scotch tape (with vacuum)

7. Example of new fixation on –X side

8. Operations on evaporators (cooling loops) • Change (weld) new connectors • Modify the pigtails to solve the interferences with LTOF • High pressure and leak tests ( 200? bars) • Mounting on external planes + checks • Cleaning (this week) • Mounting on inner tracker (to be done)

9. AMS TRACKER ADP Annex 1 Modification of the top evaporator to provide more clearances with the tracker cables Fig. 1 below is showing the interference between one of the copper blocks of the top evaporator with the tracker cables in the vicinity of the Star Tracker support

10. Copper block before and after the modification on ladder Positions 10 M and 10P. Work done by PhB/ EP 16/7

11. Incompatibilities between locations of LTOF patch panel and pigtails of the tracker lower cooling pipes and collision.

12. Need to modify the lower cooling loops by replacing the last pigtails by a simple S.

13. AMS TRACKER ADP Annexe 2 Modification of one evaporator loop to solve interference with Lower ToF (LToF) 6mm down Twisting in this area

14. New connectors welding, pigtails suppression, tests Bart Verlaat Erno

15. Flush with CO2 • Rinse with IPA • Flush with CO2 Cleaning (this week) Aswin Pauw NLR

16. Cleaning (this week)

17. Mount outer evaporators on planes + check support geometry • Two types of fixation: • Plane only: on thermal bars + plane • Shared: brackets on conical flange + plane modifications

18. Fixation on thermal bar (upper part on plane not shown) Screw securing: helicoils + glue ChoTherm Spring coupling Thermal bridge

19. Six damaged helicoils or threads were repaired

20. Riveting and gluing of the upper parts of fixations

21. Two pins to secure cable connectors Five different sizes ! (clearance from 0 to 1 mm)

22. Trial assembly of the whole bracketery supporting the evaporators. Design & fabrication of new and missing brackets • New brackets • Jigs tosimulate the fixation of the lower part of brackets to conical flange • Check if it fits • Maarten Weber … in order to avoid bad surprises at final integration..

23. Supporting brackets for evaporator connectors • New loop connectors need a better fixation (magnetic force twice ~ 5 N )

24. Tracker crate balconies Lower parts installed with controlled torques ATS exists

25. Remaining off-line operations(in clean room) • Evaporators (cooling loops) • Cleaning (in progress) • Outer planes • Terminate test and installation of bracketry (in progress) • Install connectors securing pins (plane 1 done) • Inner Tracker • Install upper inner cooling loop • Glue and prolongate DS thermal sensor chain • Install evaporators supporting brackets on conical flange • Install thermocouples for TVT tests (locations to be defined)

26. Missing procurements • Mylar patches on M10 nuts (ship to US) • Structural screws (NASA) • Shims for tracker feet. (clarify situation) Cold Vacuum Case Installation Opinion : • No solutions are seen if we want no stress on feet during mission. (impossible to mount the feet under stress) • If one accept stress on the feet during mission, mounting the feet with pumped VC can be considered.

27. Preparation of final integration • Update of integration procedures (ATS, S. Lucidi, FC, EP, DR) taking into account what we have learned in pre-integration and the limitations imposed by the real vacuum case: • Limitation of RAS rotation • Field mapping / Need for special protection • Cryogenic services to VC • Final cabling