1. CN2PY Proton Beam Transfer B.Goddard reporting for F.Velotti, A.Parfenova, R.Steerenberg, K.Cornelis, W.Bartmann, V.Kain, E.Carlier, V.Mertens, A.Alekou, L.Jensen, M.Meddahi, A.Kosmicki, J.Osborne, I.Efthymiopoulos

2. Outline Assumptions Stage 1 beamline LSS2 extraction feasibility – Simulation and MD results Open questions and discussion items

3. LAGUNA-LBNO: assumptions 1.Present SPS with 400 GeV CNGS-type beam (400-500 kW) 2.SPS to 750 kW (7e13 ppp at 400 GeV every 6 s) 3.New 2.0 MW proton driver (LP-SPL plus new 50 GeV “HPPS”) Ideally common target and secondary beam infrastucture for all LAGUNA-LBNO phases (lead times, cost, radiation, …) Implies designing beamline layout from SPS with future proton driver already in mind 2 nd integer extraction with 5 ms pulse maybe OK for experiment, but not for SPS (2-3% beamloss expected)  fast extraction needed 3

4. Beam transfer ‘baseline’ assumptions Target in SPS North Area – Stage 1 and 2: 400 GeV extraction from SPS – Stage 3: connection to ~50 GeV HP-PS Investigating options for extraction from SPS LSS2 – New kickers in LSS2 – Reuse of existing kickers in LSS6 Upgrade of TT20 and new beamline sections

5. Extraction from LSS2, target in North Area I.Efthymiopoulos (LP)- SPL HPP S CNGS Near detector Target (0.75-2MW) ν beam to Pyhasalmi 5

6. Beamlines in stage 1 A.Kosmicki & J.Osborne Upgraded TT20 New section to target

7. A.Kosmicki & J.Osborne Beamlines in stage 1 Upgraded TT20 New section to target

8. A.Kosmicki & J.Osborne H-bend 15 deg V-bend 10 deg

9. Arc length and dipole tilt Large simultaneous vertical and horizontal bend Assume 1.9 T, 6.0 m long dipoles (similar to CNGS) Need large tilt angle of about 35 degrees Shortest arc length ~290 m (9 half-cells of 32 m length, 36 dipoles) H bending radius (effective) 1100 m Need ~50 dipoles if separated H and V bends (~420 m)

10. Branching from TT20: switch length TT40/TT41 switch ~40 m long (400 GeV p+) Will need very similar insertion in TT20 TT40/TT41 (CNGS/TI 8) 8x MBSG switch magnets, ~40 m

11. Branching from TT20 Ideally before first TT20 splitter magnets – Optics progressively more and more screwed up – Very high radiation – Aperture limits But little space for new 40 m drift...

12. Branching from TT20 at 400 GeV Switch magnet here ? ~5 m free 22 22 22 22 22 ~7 m free Switch before  2 means extra 110 mrad of new vertical bends (12 dipoles, 130 m) Will need to look at redesign of upper part of TT20 to accommodate the switch

13. LAGUNA-LBNO: extraction from SPS Option 1: add new kickers into LSS2 – 2 new MKE kickers added – issues of extra impedance, layout changes Option 2: reuse existing machine kickers – Use existing kickers in one SPS LSS with existing septa in LSS2 13

14. New enlarged MKE-X kickers in 216 New MKE-X kickers 100 GeV/c, 8 um  x, ±4  envelopes

15. LSS2 layout To NA Bumper Transverse damper Magnetic septa MST Upgraded Protection device TPSG Magnetic septa MSE Possible LSS2 layout Transverse damper Shielding TCE (displaced) Electrostatic septa ZS (displaced) New MKEX

16. LSS2 MKE-X for 400 GeV extraction…  To note:  4 kA OK (but problematic if pulse length of 22  s…)  3.6 – 4.0 us rise time excludes present FT beam beam momentumGeV/c400 B.rhoTm1336.5 cm/s3.00E+08 mu0N/A21.26E-06 required kickrad4.00E-04 Magnet impedanceOhm6.25 number of cells14 V aperturem0.032 H aperturem0.170 cell lengthm0.239 magnet lengthm3.346 total tank lengthm4.346 average fieldT0.160 currentA4058 switch voltage (2U)V50722 inductanceH2.24E-05 capacity per cellF40.85E-09 total capacityF5.72E-07 rise time (L/Z)s3.58E-06

17. Non-local extraction Very difficult to integrate kickers into LSS2, so alternative idea to use kickers elsewhere in SPS: LSS2 extraction using LSS1 MKP kicker (limited to 100 GeV) – Easiest to configure and test with beam (no interlocking issues) – Simulations competed, MD tests done 17/09/12, beam extracted to TT20 – Active test program continuing LSS2 extraction using LSS6 MKE kicker (to 450 GeV) – Constrained by interlocking and energy limits – Only possible to test with HiRadMat beam (440 GeV), late in 2012 – 400 GeV in theory easier than 100 GeV (beams factor 2 smaller transversely) – Simulations in progress, MDs being organised LSS2 extraction using LSS4 MKE kicker (to 450 GeV) – Not being actively looked at, at the moment

18. Phase advances – 2012 optics LSS1->LSS2: LHC Q26 lss1_deltamu = 4.1895 (68.22 deg) ; kick_2 = 0.929 ; LSS6->LSS2: CNGS lss6_deltamu = 9.0675 (24.29 deg); kick_6 = 0.411 ; LSS6->LSS2: LHC Q26 lss6_deltamu = 8.8998 (323.94 deg); kick_6 = -0.589 ; LSS6->LSS2: LHC Q20 lss6_deltamu = 6.8491 (305.60 deg); kick_6 = -0.812 ; Possibility to use “QSPLIT” to adjust phase advance between LSS6 and LSS2

19. Kicker LSS1 Extraction LSS2 ~1.2 km Simulations – LSS1->LSS2 Bump and extraction trajectories (110 GeV, 8 um, ±5  envelopes)

20. LSS6 – LSS2 2.2 km kicked beam Closed-orbit bump in LSS1

21. Zoom in LSS2 extraction region Including orbit from quadrupole misalignments (100  m)

22. Aperture quantification, with SPS orbit 110 GeV Bumped beam 100 GeV Bumped beam 110 GeV Extr. beam 100 GeV Extr beam 5.1-5.2  3.7-3.8  5.7-5.8  4.5-4.6 

23. SPS measurements (I) 4/09/2012: LSS1 – LSS2 phase advance checks Phase advance scatters within ±15° around value expected from linear lattice (20.5°) No tune dependence on oscillation amplitude or intensity Phase advance scatters within ±15° around value expected from linear lattice (20.5°) No tune dependence on oscillation amplitude or intensity

24. SPS measurements (II) 17/09/2012 Extraction test MKP MST/MSE

25. First fast extraction in LSS2 MKP kickers pulsed using timing event and pre-pulse (no beam from PS) Beam extracted into TT20 using calculated settings – MKP on at 52 kV for three generators – MST on at 0.5 mrad – MSE on at 1.92 mrad Needed then to trim MSE up by few % (as usual) BTV.210026BTV.210352

26. Aperture and loss scans 4e11 p+, 110 GeV, blown up to 7 um.mrad to approach CNGS parameters Issue seen with too-fast bumper functions, corrected

27. Effect of bumper function correction Extraction losses (extraction time 2400 ms) Before correction After correction Losses from bump overshoot

28. Extracting 7 um.mrad with 10% more MKP kick strength (as for 100 GeV beam) No measurable extraction losses (extraction time 2400 ms) Managed to get SPS orbit acquisition for last turn Some coupling into V? To understand

29. Other extraction aspects Other feasibility aspects being considered: – MKE6 rise time of 6 us Can reduce to 2  s without adding any more kickers to SPS (switches + TMRs) Feasibility of single long extraction (20  s), with asymmetric filling pattern? – Interlocking and machine protection issues Beam Interlock Controllers, interlocking logic, Energy Tracking Conceptual solution already defined with interlocking team All machine protection implications to be examined (MPP 28/09/12) – Kicker HW upgrades needed for double extraction Charging supplies, PFNs, cabling, … – Kicker control updates also required Pre-pulses, timing, cabling, … – Extraction region BI for both fast and slow beams Screens, BPMs, BLMs, BCTs No major feasibility issues identified to date

30. Summary for “non-local” extraction Concept shown to work, on paper and in machine. – Clean extraction achieved (for low intensity beam only) LSS1 MKP can extract 100-110 GeV in LSS2 with ε n =7 μm – Losses scaled to CNGS intensity look same order of magnitude as those seen now in LSS4 (higher intensity will only make things worse) LSS6 MKE kickers will be tested, will allow 450 GeV – Looks OK on paper and losses should be lower – Present rise time of 6-7  s precludes double extraction – To investigate impact of 20  s pulse (beam dyanmics, target, losses,...)

31. Open questions /discussion Synergy with SBL to be clarified (and then managed). Potential overlap or competition for resources with AWAKE project to be clarified – e.g. looking at re-using CNGS beamline or components. Other potential areas of overlap are LIU (e.g. proposed upgrade of MKP kickers for ions, which may not be compatible with use as fast extraction kicker). Studies for 50 GeV beam transport from HP-PS to start – Complete new tunnel and beamline (conceptually easy, but costly) – New beamline in SPS tunnel (cheaper, but may not be feasible) – Using SPS as 50 GeV transfer line (cheapest, needs study)

32. Conclusions Beamline studies in progress for stage 1 – Target coordinates known, other input still needed (especially beam parameters at target) – Branching from well before TT20 splitter ideal, but means a lot more beamline. Will investigate redesign of upper part of TT20 Beamline work for HP-PS will start, with first ideas on machine configuration – Different options to study Fast non-local extraction from LSS2 (still) looks feasible – Should be able to conclude in 4-6 weeks on use of MKE in LSS6 – Machine protection and 20  s pulse length main feasibility issues