BNL FNAL LBNL SLAC LARP 9 th Collaboration

BNL - FNAL - LBNL - SLAC LARP 9 th Collaboration Meeting Oct. 17 -19, 2007 LQ Goals & Design Summary Giorgio Ambrosio OUTLINE: • LQ goals • LQ design status LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 LQ Goals and Design Study Summary – G. Ambrosio

LQ Goals GOALS: • Gradient: 200+ T/m • Aperture: 90 mm • magnet length: 4 m Timeframe: • Performance and reproducibility by the end of 2009 LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 LQ Goals and Design Study Summary – G. Ambrosio 2

LQ Goals + • The LQ may also be an opportunity to test some accelerator features (such as alignment, unrestricted cooldown) in long Nb 3 Sn magnets Questions for discussion: Is this important, necessary, negligible? What features? Could an LQ with accelerator features become QA? LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 LQ Goals and Design Study Summary – G. Ambrosio 3

The Road to the LQ Technological Quadrupoles, Long Quad. Design Study Long Racetrack Long mirror LQ task (FY 08) Practice coils Long Quadrupole LQ 01, LQ 02, LQ 03 LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 LQ Goals and Design Study Summary – G. Ambrosio 4

Magnetic Design • Coil layout = TQs Parameter • Iron yoke design depends on mechanical structure – Collar design with iron yoke up to the ends – Shell design may have ss pads LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 Unit TQC TQS N of layers - 2 N of turns - 136 cm 2 29. 33 Coil area (Cu + non. Cu) 4. 2 K temperature Quench gradient T/m 221 234 Quench current k. A 13. 3 13. 2 Peak field in the body at quench T 11. 5 12. 0 Peak field in the end at quench T 11. 9 11. 8 m. H/m 4. 56 5. 03 k. J/m 406 438 Inductance at quench Stored energy at quench 1. 9 K temperature Quench gradient T/m 238 252 Quench current k. A 14. 4 Peak field in the body at quench T 12. 4 12. 9 Peak field in the end at quench T 12. 9 12. 7 472 5 511 LQ Goals and Design Study Summary – G. Ambrosio Stored energy at quench k. J/m

Conductor • Cable: – LQ cable design = TQ cable design • Strand: – RRP 54/61 for LQ 01 • Strand used in TQS 02 coils (also in TQE 02) and LR • Good performance at 4. 5 K • Limited performance at 1. 9 K under investigation – Higher number of subelements considered for following LQs More info and • Options: 114/127, 108/127, … • Possible CERN-LARP collab. LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 discussion in the Materials session LQ Goals and Design Study Summary – G. Ambrosio 6

Mechanical Design TQC Hybrid design TQS Both TQ designs are options for the LQ, the hybrid design cannot be considered because lacking short models LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 LQ Goals and Design Study Summary – G. Ambrosio 7

Mechanical Design • Following presentations will show details of the LQ Support Structure options • LQ Support Structure Review – Nov 28 -29, at BNL – Originally thought of as Selection Review, – Presently considered as Plan Review More on these topics at the end of the session LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 LQ Goals and Design Study Summary – G. Ambrosio 8

Coil Fabrication Technology • LQ coils = TQ coils + minor modifications – Pole material: Ti-Al-V (as TQS 02 coils, also used in TQE 02) – Ground insulation: Kapton wrap (as TQC coils) • 1 k. V Hi-pot test – Soldering to traces outside of the magnet (new features) – Outer layer glued to the coil (as TQS coils) – Pins to lock inner and outer layer • Goal: to improve coil fabrication process reliability – Insulation: LQ 01 will use TQ sleeve • Tested also on LR LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 Nb. Ti leads: 0. 7 1 mm ? LQ Goals and Design Study Summary – G. Ambrosio 9

Quench Protection • Goal: – MIITs < 7. 5 Temp < 380 K • Quench protection parameters (4. 5 K) – – Dump resistance: 60 m. W 100% heater coverage Detection time: ~5 ms Heater delay time: 15 ms LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 (extract ~1/3 of the energy; Vleads ~ 800 V) ( heaters also on the inner layer) based on TQs with I > 80% ssl LQ Goals and Design Study Summary – G. Ambrosio 10

Coil Instrumentation (…in progress) Voltage taps: – Inner layer: 4 VTs more than TQC (+5 -1) • Goals : splice, pole-midplane blocks, pole turn (lead end, return end, layer-ramp, straight section), 2 nd turn – Outer layer: Same as TQs • Goals: splice, pole turn (lead end, return end, layer-ramp) • Strain gauges as TQS • Protection heater on both layers • Will need two traces (1. 5 m each) for layer – May still be too much… Work in progress • Bubbles: plan tests at 4. 5, 2. 5 K and 1. 9 K (at the end) – Bubble proof heater design? LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 LQ Goals and Design Study Summary – G. Ambrosio 11

Next • Complete LQ Design Study Report before the LQ Support Structure Review LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 LQ Goals and Design Study Summary – G. Ambrosio 12

Next talks Session 5 B Magnets - LQ session 1 Chair Ambrosio Redwood Room- C/ D 9: 00 9: 20 Ambrosio LQ goals and DS summary 9: 20 9: 40 Schmalzle LR summary and LQ work at BNL 9: 40 10: 00 Nobrega LM summary and LQ work at Fermilab 10: 00 10: 20 all Discussion 10: 20 10: 35 Coffee Session 6 B Magnets - LQ session 2 Chair Ambrosio Redwood Room- C/ D 10: 35 10: 55 Ferracin LQ support option - segmented shell 10: 55 11: 15 Bossert LQ support option - collars 11: 15 11: 35 Ambrosio LQ plans 11: 35 11: 55 all LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 Discussion LQ Goals and Design Study Summary – G. Ambrosio 13

Appendix LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 LQ Goals and Design Study Summary – G. Ambrosio 14

LQ inner layer A 5 A 4 A 6 A 10 NEW A 3 A 9 500 mm ? Q u a d ra n t 3 In n e r A 1 A 2 A 7 NEW NEW A 8 GOALS: Splice: A 1 -A 2; pole-midplane blocks: A 3&A 5 (redundancy); lead end: A 6 -A 7 Return end: A 8 -A 9; layer-ramp: A 10; straight section vs. ~ends: 4 VTs NEW 2 nd turn: NEW LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 LQ Goals and Design Study Summary – G. Ambrosio 15

TQs Heater Delay & Detection Time • Heater delay time: t < 10 ms close to quench plateau; t < 15 ms at I = 62% Issl • Detection time: 3 - 11 ms during TQS 01 c training – Flux jumps up to 600 m. V with MJR cable msec TQC 01 TQS 01 c LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 and Design Study Summary – G. Ambrosio TQC 01 protection heater studies by using spot heaters to initiate LQ the. Goals quench. 16

MIITs Limit • Impact on quench performance of high -MIITs quenches (TQS 01 c) • • • + 4% after 8 MIITs - 2. 9% after 8. 1 MIITs - 7. 4% after 8. 7 MIITs - 18. 4 after 9. 5 MIITs Small bumps at 7. 5 MIITs • During TQC 01 test, one QI vs. T measurement I: 5000 A , QI: 9. 05 MIITs, LARP Collab Mtg – SLAC, Oct. 17 -19, 2007 Peak Temp: 340 K LQ Goals and Design Study Summary – G. Ambrosio 17