Vision from LHC to HLLHC operation Lucio Rossi

Vision from LHC to HL-LHC operation Lucio Rossi For the HL-LHC project The Hi. Lumi LHC Design Study is included in the High Luminosity LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404.

LHC performance evolution (guess!) 0. 75 1034 cm-2 s-1 50 ns bunch high pile up 40 1. 5 1034 cm-2 s-1 25 ns bunch pile up 40 1. 7 -2. 2 1034 cm-2 s-1 25 ns bunch pile up 60 Technical limits (experiments, too) like : 50 25 ns LRossi@R 2 E Workshop 14 Oct 2014 2

Lumi evolution till 2035 (no learnimg…) 5 1034 cm-2 s-1 , levelling, 250 fb-1/y, 3000 fb-1 When learning curve is folded in (250 f-1/y in 2028) need to plan eventually 300 fb-1/y, with 7 -7. 5 1034 cm-2 s-1. Design should also able to allow to 4000 fb-1, if needed. LRossi@R 2 E Workshop 14 Oct 2014 3

High lumi insertions: higher, larger. . . Longer Quads; Shorter D 1 (thanks to SC) LHC triplet 70 mm 8 T 11 k. A ATLAS CMS E. Todesco HL LHC triplet > 12 T 150 mm 15 -17 k. A ATLAS CMS LRossi@R 2 E Workshop 14 Oct 2014 4

The HL-LHC Nb-T imagnet zoo… D 1 (KEK) D 2 (INFN) Nested orbit corrector (CIEMAT) HO correctors: superferric (INFN) See WP 3 webpage Todesco et al. Lucio Rossi@LMC 184 E. 9 July 2014 Q 4 (CEA) D 2 corr 5

Effect of the crab cavities • RF crab cavity deflects head and tail in opposite direction so that collision is effectively “head on” and then luminosity is maximized • This are COMPACT CC, completely new design! Must work synchronized (0. 001 ) on each side of the IP! Lucio Rossi@ICHEP 2014 6

Latest cavity designs toward accelerator Coupler concepts RF Dipole: Waveguide or waveguide-coax couplers Concentrate on two designs Double ¼-wave: Coaxial couplers with hook-type antenna 4 -rod: Coaxial couplers with Present baseline: 3 cavity /cyomodule different antenna types 4 cavity/cryomod is under study for Crab Kissing Lucio Rossi@ICHEP 2014 TEST in SPS under preparation (A. Mac. Pherson) 7

P 2 - DS collimators ions – 11 T (LS 2 -2018) 11 T Nb 3 Sn Lucio Rossi@ICHEP 2014 FNAL - CERN 8

Low impedence collimators(LS 2 & LS 3) Maybe already in LS 2 New material: Mo. Gr Lucio Rossi@LMC 184 9 July 2014 Reduce impedance by > 2) S. Redaelli et al. 9

LRBBW: an enabling tool that needs a NOT baseline (yet) definitive test 9. 3 Test using an adapted collimator Test is expensive! The final system cannot be an electric wire embedded in a jaw! e-lens used as e-wire However wee need > 200 A m! Lucio Rossi@LMC 184 9 July 2014 10

Controlling halo diffusion rate: hollow e-lens (synergy with LRBBCW) NOT baseline (yet) Promises of hollow e-lens: 1. Control the halo dynamics without affecting the beam core; 2. Control the time-profile of beam losses (avoid loss spikes); 3. Control the steady halo population (crucial in case of CC fast failures). Remarks: - very convincing experimental experience in other machines! - full potential can be exploited if appropriate halo monitoring is available. Lucio Rossi@LMC 184 9 July 2014 11

Crystal collimation: a new paradigme in collimation (DS – partially – and primary NOT baseline (yet) Lucio Rossi@LMC 184 9 July 2014 12

Eliminating Technical Bottlenecks Cryogenics P 4 - P 1 –P 5 IT IT RF RF New Plant 6 k. W in P 4 IN LS 2 Two new 18 k. W Plants in P 1 and P 5 IT IT IT Lucio Rossi@LMC 184 9 July 2014 13

New IR Cryo-scheme (sepration IR-Arc) L. Tavian R. Van Weelderen S. Claudet Lucio Rossi@LMC 184 9 July 2014 14

Displacing EPC and DFB in the adjacent TDZ tunnel ( 500 m away) via SC links It si also a TEST! 4. 5 K Q 11, Q 10…Q 7 DFBM Q 6 DFBA D 4 D 3 Q 5 Q 4 IP 7 DQR IP 6 8. 75 m RR 73 1 m Warm magnets (PCs in UJ 76) RR 73 Lucio Rossi@LMC 184 9 July 2014 15

L = 20 m (25 2) 1 k. A @ 25 K, LHC Link P 7 Feb 2014: World record for HTS transport current (A. Ballarino) Lucio Rossi@LMC 184 9 July 2014 16

Parameter Beam energy in collision [Te. V] Nb Nominal LHC (design report) 7 1. 15 E+11 HL-LHC 25 ns HL-LHC 25 ns HL-LHC 50 ns (standard) (BCMS) 7 7 7 2. 2 E+11 2. 2 E 11 3. 5 E+11 nb 2808 27481 2604 1404 Number of collisions at IP 1 and IP 5 2808 2736 2592 1404 5. 7 E+14 1. 03 590 12. 5 0. 15 2. 50 1. 13 E-04 7. 55 E-02 18. 5 20. 4 3. 14 0. 305 0. 829 3. 3 E-03 1. 1 E-02 6. 80 E+34 18. 52 E+34 198 5. 00 E 34 146 1. 31 7. 6 4. 9 E+14 0. 89 590 11. 4 0. 15 3 2. 50 1. 13 E-04 7. 55 E-02 17. 2 16. 1 2. 87 0. 331 0. 838 4. 7 E-03 1. 4 E-02 8. 44 E+34 21. 38 E+34 454 2. 50 E+34 135 1. 20 18. 0 Ntot 3. 2 E+14 ATS required beam current [A] 0. 58 x-ing angle [μrad] 285 beam separation [σ] 9. 4 * β [m] 0. 55 εn [μm] 3. 75 εL [e. Vs] 2. 50 r. m. s. energy spread 1. 13 E-04 r. m. s. bunch length [m] 7. 55 E-02 IBS horizontal [h] 80 -> 106 IBS longitudinal [h] 61 -> 60 Piwinski angle 0. 65 Geometric loss factor R 0 without crab-cavity 0. 836 Geometric loss factor R 1 with crab-cavity (0. 981) beam-beam / IP without Crab Cavity 3. 1 E-03 beam-beam / IP with Crab cavity 3. 8 E-03 Peak Luminosity without crab-cavity [cm-2 s-1] 1. 00 E+34 Virtual Luminosity with crab-cavity: Lpeak*R 1/R 0 [cm-2 s-1] (1. 18 E+34) Events / crossing without levelling w/o crab-cavity 27 Levelled Luminosity [cm-2 s-1] Events / crossing (with levelling and crab-cavities for HL-LHC) 27 Peak line density of pile up event [evt/mm] (max over stable beam) 0. 21 Lucio Rossi@LMC 184 9 July 2014 Levelling time [h] (assuming no emittance growth) - 6. 0 E+14 1. 09 590 12. 5 0. 15 2. 50 1. 13 E-04 7. 55 E-02 18. 5 20. 4 3. 14 0. 305 0. 829 3. 3 E-03 1. 1 E-02 7. 18 E+34 19. 54 E+34 198 5. 00 E+34 138 1. 25 8. 3 Collision values Baseline Parameters (last PLC) 17

The Achromatic Telescopic Squeezing (ATS) scheme Small b* is limited by aperture but not only: optics matching & flexibility (round and flat optics), chromatic effects (not only Q’), spurious dispersion from X-angle, . . A novel optics scheme was developed to reach un-precedent b* w/o chromatic limit based on a kind of generalized squeeze involving 50% of the ring (S. Fartoukh) b*= 40 cm b*= 10 cm Proof of principle demonstrated in the LHC down to a b* of 10 -15 cm at IP 1 and IP 5 The new IR is sort of 8 km long ! ATS is not an option is critical for the upgrade; implementation in Run II or Run III is beneficial! Lucio Rossi@LMC 184 9 July 2014 18

The ``crab-kissing’’ (CK) scheme (2/5) HL-LHC w/o CK scheme: Plan A (solid) and Plan B(dotted) - 12. 5 MV crabs in X-plane, round optics (15/15 cm), sz =7. 5 cm (Plan A) - or bb wire, flat optics (50/10 cm), sz =10 cm (Plan B) “HL-LHC+” with CK scheme and Gaussian bunch profile. . adding crab-cavities to Plan B in X and || planes (6 MV+7 MV) “HL-LHC++” with CK scheme and rectangular bunch profile. . . adding a new 800 MHz RF system (still keeping sz =10 cm) (S. Fartoukh)@ECFA HL –LHC Exper. Workshop, Aix-les-Bains 7 October 2013 z [m] w. r. t. IP A net gain by a factor 2 at each step. . at nearly constant integrated performance Lucio Rossi@LMC 184 9 July 2014 19

Operation & Intensity • Levelling cycle • Beam intensity limitation(s) • To be assessed in next LHC run • TDIS in LS 2 (don’t like too small emittance beams!) • Heating of kickers (MKI): new high Tc ferrite and coating for e-clouds (prototype installed in LS 2). Lucio Rossi@LMC 184 9 July 2014 20

Efficiency for Ldt • All our assumptions are based on forecast for the operation cycle: 50% R. De. Maria, RLIUP High reliability and availbility are key goals Lucio Rossi@LMC 184 9 July 2014 21

Integral luminosity: the final goal of HL_LHC • M. Brugger

Global Workshop Objectives Understand availability limitations due to radiation effects (SEE, TID, DD) as well as other effects onto accelerator equipment and quantify the required equipment performance to reach the luminosity goals Run 2, Run 3, HL-LHC. Identify what is required (tools, facilities, expertise) to quantify and mitigate radiation effects on equipment. Identify appropriate mitigation measures: radiation tolerant developments (tunnel electronics, PC), displacement of sensitive equipment (superconducting links etc. ) and other aspects. Identify the long-term requirements for electronic systems. Address IR 3 -IR 7 life time issues linked to radiation and equipment maintenance planning. Understand how development of electronics for radiation environment is addressed in the LHC experiments.

Global Workshop Objectives Understand availability limitations due to radiation effects (SEE, TID, DD) as well as other effects onto accelerator equipment and quantify the required equipment performance to reach the luminosity goals Run 2, Run 3, HL-LHC. Identify what is required (tools, facilities, expertise) to quantify and mitigate radiation effects on equipment. Identify appropriate mitigation measures: radiation tolerant developments (tunnel electronics, PC), displacement of sensitive equipment (superconducting links etc. ) and other aspects. Identify the long-term requirements for electronic systems. Address IR 3 -IR 7 life time issues linked to radiation and equipment maintenance planning. Understand how development of electronics for radiation environment is addressed in the LHC experiments.

Workshop Goals Aiming for high availability Radiation effects Single Event Errors (SEEs) LS 1 focus on mitigation From MITIGATION to PREVENTION Cumulative (long-term) damage (TID, DD) so far not encountered at LHC (experience from injectors!) Equipment failures (focus on electronics components) experience, development needs, options Components reaching the end of life with and without radiation 25

Workshop Goals Concerns for what to do next, but also in view of 22 years of LHC: we need R&D NOW! What needs to be done up to LS 2/LS 3 and for HL-LHC Radiation damage and intervention concerns in IR 3/7 Design/test choices and synergies to be exploited Requirements to reach the HL-LHC target Availability Expertise & Facilities Developments & Qualification Needs 26

Needs and Goals In view of the 4 Workshop Sessions Session-1: Fundamentals of R 2 E and Availability Radiation Monitoring & Test Facilities: improve/operate R 2 E Expertise (LHC, Injectors, Experiments): keep & develop Availability: fault tracking, impact analysis: improve/adopt 27

Needs and Goals In view of the 4 Workshop Sessions Session-2: Concerned Equipment: up to LS 2/LS 3/HL-LHC Development needs and R 2 E requirements: R 2 E structure? Maintenance and lifetime (with & w/o. rad. ): What is known and what needs to be? How to improve availability: What can and has to be done? 28

Needs and Goals In view of the 4 Workshop Sessions Session-3: IR 3/7 Damage/Maintenance Issues Failure risks due to radiation/environment: is there any show-stopper? Needs: monitoring, handling, testing: what is ok and what needs to be improved? Maintenance, life-time & mitigation: what is the equipment requirement/strategy? 29

Needs and Goals In view of the 4 Workshop Sessions Session-4: Long-term strategy Mitigation/Prevention strategy & needs: are we on the right track? SCL & rad-tol PC options/needs/roadmap: what is the (combined) best strategy? Required developments & synergies: what are and can be common grounds? 30

SC links removal of EPCs, DFBs from tunnel to surface (or new gallery? ) 2 150 k. A 1 pair 700 m 50 k. A – LS 2 4 pairs 300 m 150 k. A (MS)– LS 3 4 pairs 300 m 150 k. A (IR) – LS 3 tens of 6 -18 k. A CLs pairs in HTS Lucio Rossi@LMC 184 9 July 2014 31

In particular: do we need to remove the Powering of the Arc magnets in IR 1 -IR 5 ?

Past Present Future Run 1: 25 fb-1 160 days HL-LHC: 210 fb-1 200 days HL-LHC: 260 fb-1 HL-LHC: 300 fb-1 200 days + 20% availability 33

R 2 E LHC Long-Term R 2 E SEE Failure Analysis 2008 -2011 Analyze and mitigate all safety relevant cases and limit global impact ~400 h Downtime / fb -1 2011 -2012 Focus on long downtimes and shielding Relocation & Shielding um ps Equipment Upgrades ~3 d ~12 dumps / fb -1 ~250 h Downtime LS 1 (2013/2014) Final relocation and shielding r ng fo imi -1 A 2 – LS ps / fb 1 S L dum 5. 0 < LS 1 -LS 2 (2015 -2018) Tunnel equipment and power converters -1 umps / fb L-LHC: < 0. 1 d H -> LS 3 -HL-LHC Tunnel Equipment (Injectors + LHC) + RRs 34

R 2 E LHC Long-Term 35

The Hi. Lumi LHC Design Study is included in the High Luminosity LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404.