LHC status and plans Mike Lamont for the

LHC status and plans Mike Lamont for the LHC team

Recent timeline 1/3 n 2008 Accelerator complete ¨ Ring cold and under vacuum ¨ n September 10 th 2008 ¨ n September 19 th 2008 ¨ n First beams around – made it to Google The incident 2008 – 2009 14 months of major repairs and consolidation ¨ New Quench Protection System for online monitoring and protection of all joints. ¨ However… ¨ 2 LHC 23/04/10 status

Magnet Interconnection Melted by arc Dipole busbar 3 23/04/10 LHC status

Joint quality During repair work in the damaged sector, inspection of the joints revealed systematic voids caused by the welding procedure. Solder No solder wedge bus U-profile bus Extensive simulations and measurements in the lab have show that there is potential for thermal run away in case of a bus-bar quench 4 23/04/10 LHC status

Joint Quality Solder used to solder joint had the same melting temperature as solder used to pot cable in stablizer Solder wicked away from cable 23/04/10 LHC status 5

To go to 7 Te. V per beam Splice consolidation is required - options under examination Everywhere 23/04/10 LHC status 6

To conclude on this issue n n n Splice issues not fully resolved To be 100% sure that we can go safely to 7 Te. V per beam - eradication of joint issue requires a complete warm-up and long shutdown (2012). The LHC beam energy will be limited to 3. 5 Te. V in 2010/2011 In the meantime n n New Quench Protection System fully deployed and tested All magnet circuits qualified for 3. 5 Te. V ¨ 23/04/10 Main bends and quads to 6000 A and looking good so far LHC status 7

Timeline 2/3 n November 20 th 2009 ¨ n November 29 th 2009 ¨ n First beams around again Both beams accelerated to 1. 18 Te. V simultaneously December 8 th 2009 LHC - highest energy collider 2 x 2 accelerated to 1. 18 Te. V ¨ First collisions seen in ATLAS before beam lost! ¨ n December 14 th 2009 Stable 2 x 2 at 1. 18 Te. V ¨ Collisions in all four experiments ¨ Limited to 2 k. A in main circuits (1. 18 Te. V) during deployment and testing of new Quench Protection System 23/04/10 LHC status 8

Timeline 3/3 2010 27 th Feb 28 th Feb 5 th March 8 th March First injection Both beams circulating Canonical two beam operation Collimation setup at 450 Ge. V 12 th March 15 th - 18 th March 19 th March 30 th March Ramp to 1. 18 Te. V Technical stop – bends good for 6 k. A Ramp to 3. 5 Te. V collision under ‘stable’ beam conditions Squeezed stable beams (with a bit of luck) 23 rd April 23/04/10 LHC status 9

Beam commissioning strategy 2010 Global machine checkout 450 Ge. V re-commissioning Machine protection commissioning Ramp commissioning Establish stable safe beams at 3. 5 Te. V Collisions at 3. 5 Te. V System/beam commissioning continued Squeeze today Collisions at 3. 5 Te. V squeezed Full machine protection qualification 23/04/10 LHC status 10

Beam 1 Beam 2 Typical pictures 12 hours Ramp 23/04/10 Problems LHC status 11

Status – 450 Ge. V n n n 23/04/10 Good beam lifetimes. Lower than nominal emittances. Optics verified and corrected to a maximum beta beat of 20 -30%. Almost in specification. Orbit adjusted to an rms of ~0. 45 mm (about +-2 mm peak to peak) Aperture Beam looks good. Some measured bottlenecks agree with model predictions Solenoids, spectrometer and compensators set up and corrected with beam. Nominal separation bumps set up LHC status 12

Status – 450 Ge. V n n Collimation system (all ring collimators) set up with ~0. 2 mm accuracy. Cleaning and protection hierarchy verified with beam (efficiency: > 99%, limited by BLM resolution with this intensity). Beam instrumentation working very well Injection, beam dumps, machine protection commissioning well advanced (but not finished) Higher intensities – work in progress ¨ 1. 1 e 11 (nominal bunch intensity) injected OK 450 Ge. V machine in good shape Excellent reproducibility 23/04/10 LHC status 13

Intensity Lifetime Pilot Bunches at 450 Ge. V n n n n 23/04/10 LHC status Corrected to golden orbit with separation bumps. . . All perturbations & excitations switched off. Tunes to nominal. Chromaticity to +4. Collimators to nominal injection settings. No trims & corrections. Emittance measured… 14

Aperture at 450 Ge. V: Kick Method Q 4 R 6 B 1 H Optics from β-beat team: Stefano, Massimo et al 23/04/10 Beam 1 βx = 117. 7 m → σx = 0. 93 mm ⇒ Ah = 10. 8 σ βy = 249. 3 m → σy = 1. 35 mm ⇒ Av =11. 1σ LHC status 15

Beam dumping systems working very well Systematic and very thorough testing and set-up in progress Kickers sweep bunches to “dilute” intensity on dump 23/04/10 LHC status 16

Collimation q Full CLEANING q Beam collimation setup at injection in 2009. cleaning efficiencies ≥ 99. 98% ~ as designed Loss at primary collimator Collimation Peak leakage to supercond. magnets t en em ur se s i a Me no 17 23/04/10 LHC status

Beam Instrumentation n The enabler – excellent Beam Position Monitors Excellent performance ¨ Very stable orbit (V drift ~ 15µm/h) ¨ n Beam Loss Monitors ¨ n BLMs correctly removes the BEAM PERMIT signal if measurements are over threshold. Almost no reliability issues observed. Profile monitors ¨ Synchrotron light, wire-scanners operational Base-Band-Tune (BBQ) system was a work horse from day one giving tune, chromaticity, coupling, feedback. 23/04/10 LHC status 18

Machine Protection System Provides the mechanism to dump the beam in around 3 turns if anything out there decides it’s had enough n Mission critical backbone Beam Interlock System ¨ Safe Machine Parameters ¨ Plus inputs to/from other systems (e. g. timing, BCT) ¨ n n Multitude of ‘user’ inputs In additions the beam drives a subtle interplay of: Beam dump system, Collimation, protection devices, RF… ¨ Instrumentation (BLMs, BCT, BPMs…) ¨ Aperture ¨ Optics ¨ Absolutely, absolutely critical 23/04/10 LHC status 19

Ramp to 3. 5 Te. V n n Successfully ramped two pilots to 3. 5 Te. V on first attempt Routinely ramp without beam loss ¨ But only low intensity n Tune feedback operational Orbit looks stable and reproducible Orbit feedback operational n Fine adjustments required for higher intensity n n Tighter parameter control ¨ Collimators to move in the ramp ¨ 23/04/10 LHC status 20

Ramp 3. 5 Te. V 7 e 9 • Energy: 450 to 3500 Ge. V 450 Ge. V • Main bend current: 760 to 5850 A • Ramp rate: 2 A/s • Length: 47 minutes 23/04/10 LHC status 21

3. 5 Te. V n Excellent stability and reproducibility ¨ ¨ ¨ n Good lifetimes Some unexpected emittance growth Some bunch length increase Orbit – rock solid Optics within tolerance and reproducible Machine protection has caught everything so far Operations and others are exploring stuff-up space ¨ Full set-up and tests still in progress. ¨ The beams definitely like it up there!

Beam 2, 3. 5 Te. V beta-beating 23/04/10 LHC status 23

The way to stable beams @ 3. 5 Te. V n Scenario with abnormally low beam lifetime created on purpose by operating the machine in an unfavorable working point (3 rd order resonance) losses are caught mainly at the betatron collimation area in LSS 7 (designed to stop particles at large oscillation amplitudes) Beam 1 LHC status 23/4/10 24

30 th March 2010 – we got away with it LHC status 23/04/10 25

Physics 48 h n We can produce long fills but we did not manage to have a programmed dump yet n Beam lifetime is excellent (>100 h) n From LHC Physics Coordinator @ LMC (07/04/2010): order of 300 mb-1/expt ¨ Several million inelastics on tape ¨ Inelastic rates typically up to ~120 Hz when optimized and ~1. 1 e 10 p/bch, ¨ Luminosity life time seen well above 20 h ! ¨ Accumulated LHC status 23/04/10 26

Physics Safe beam: 2 bunches of 1. 2 e 10 Luminosity: ~2 e 27 cm-2 s-1 23/04/10 LHC status 27

Squeeze n Now squeezed to 2 m. in all four experiments n Factor 5 in luminosity seen as expected n Limited to 2 m by aperture (energy) & beam-beam considerations n Measured b* close to expectations n Hope for first physics fill squeezed today LHC status 23/04/10 28

Systems availability • System availability is remarkable but every problem at high energy costs time need to ramp down and cycle the magnets turn around time is larger than 4 hours Typical examples: • Vacuum leak on the bellows of the movable stoppers in the injection transfer lines (replaced) • Cryogenics stops in (cold compressors, de-icing) • Spurious triggers of the QPS observed on the main quadrupoles • Current lead temperature controls failures • ++ huge potential problem space • Operational procedures - eek! 23/04/10 LHC status 29

OUTLOOK 23/04/10 LHC status 30

2010 continued n Beam commissioning ¨ n Consolidation & physics at the safe beam limit ¨ n n Immediate aim: colliding, safe, stable, squeezed beams 3 e 10 per beam at 3. 5 Te. V Full machine protection qualification Phased intensity increase and associated machine protection qualification Establish secure and reproducible operations and fully field test ¨ Moving very, very carefully ¨ 23/04/10 LHC status 31

The path to 2 MJ Main challenge will be learning to operate safely with destructive beams Approved steps to 2 MJ 23/04/10 LHC status 32

What you can TT 40 Damage during 2004 High Intensity SPS Extraction / Goddard, B ; Kain, V ; Mertens, V ; Uythoven, J ; Wenninger, J Or what you can do with 2. 9 MJ During high intensity extraction on 25/10/04 an incident occurred in which the vacuum chamber of the TT 40 magnet QTRF 4002 was badly damaged. The beam was a 450 Ge. V full LHC injection batch of 3. 4 1013 p+ in 288 bunches, ~4. 4 e 12 at 3. 5 Te. V 23/04/10 or around 1031 cm-2 s-1 LHC status 33

Near future looks like being… n Run 2010 at 3. 5 Te. V ¨ n n Short winter stop 2011 ¨ n 23/04/10 Run at 3. 5 Te. V with the aim of delivering at least 1 fb-1 2012: long shutdown (~1 year) ¨ n Estimate integrated luminosity 100 - 200 pb-1 Fix all splices properly – LHC good for 7 Te. V (give or take some dipole re-training). Head for nominal performance LHC status 34

2011 3. 5 Te. V: run flat out at ~100 pb-1 per month 16% nominal beam intensity Aim to deliver around 1 fb-1 23/04/10 LHC status 35

To 2014 – optimistic n n n LHC status 2012: splice consolidation 2013: 6. 5 Te. V ~25% nominal intensity 2014: 6. 5 Te. V ~40% nominal intensity 23/04/10 36

Conclusions 1/2 n n A lot of hard work over the years has enable a truly impressive period of initial commissioning with beam. Initial indications are that the LHC: is reproducible; ¨ magnetically well understood; ¨ optically in good shape; ¨ is armed with a mighty set of instrumentation, software, and hardware systems. ¨ n n Lots still to sort out, in particular… Operations, controls, instrumentation etc. have the capability to unnecessarily stress the machine protection system – issues must be resolved. Long way to go before we are ready to move too far above the safe beam limit 23/04/10 LHC status 37

Conclusions 2/2 n First collisions at 3. 5 Te. V squeezed very soon ¨ n n n 1028 cm-2 s-1 Followed by a running period around the safe beam limit Rigorous preparation for moving beyond the safe beam limit. Careful stepwise increase in intensity with each step up in intensity to be followed by an extended running period. Targets for the next two years clearly defined. The LHC looks like being beautiful machine… Big thanks are due to all the teams involved. A remarkable effort has been repaid with remarkable progress. 23/04/10 LHC status 38