1. 18 July 20071 Reminder Dilution kicker system MKB is staged (2H, 2V) –Limits extracted intensity at 7 TeV to 50% of nominal –For 25ns spacing, this is a limit on single bunch intensity, NOT on total in LHC –Not an issue for “Stage I” : could safely dump full beam intensity up to about 2 TeV – (no interlock - rather unlikely to be needed in first few months…) BTVDD trace – full dilutionBTVDD trace – staged MKB Allowed dumped intensity (staged MKB)

2. 18 July 20072 Safety critical aspects of the LBDS Signal from beam interlock system (test in HWC/RR) –No trigger = no beam dump Energy tracking –Potentially catastrophic (whole beam at “any” amplitude) MKD retriggering (test in HWC/RR) –No retriggering could put whole 7 TeV beam at ~10  TCDQ setting –Wrong w.r.t. orbit exposes LHC arc / triplets / collimators. System self-tests and post-mortem –Undetected ‘dead’ MKD severely reduces reliability Aperture, optics and orbit –Dump with bad orbit could damage extraction elements MSD, TCDS or MKB MKD – MKB connection and sweep form –Insufficient dilution could damage TDE, BTVDD and TDE entrance window Abort gap ‘protection’ –Beam in the abort gaps risks quench, or TCT/LHC damage if TCDQ position error Fault tolerance with 14/15 MKD –The system is designed to operate safely with only 14 out of the 15 MKDs Nearly all aspects need beam commissioning (validation or optimisation)

3. 18 July 20073 Before first extraction… Circulating beam, 1 pilot at 450 GeV Rough timing and revolution frequency –Adjust RF synch  MKD kick delay,  signal from IR6 BPM (UA access for each delay trim!) Optics and other measurements in IR6 –Beta, dispersion, orbit correction, stability Commission dedicated LBDS BDI for circulating beam –Synch BPM, BLMs (MKD, MSD, TCDS, TCDQ), check direct LBDS interlock BLM Aperture measurement with circulating beam –MSD, TCDS, MKD, TCDQM 15.3 mm (n1=6.5) 20.8 mm (n1=7.0) Opening for circulating beam (H plane) at TCDS and MSD

4. 18 July 20074 Before first pilot ramp…i Extracted beam: 1 pilot @ 450 GeV (inject & dump) First extraction –Into “Inject & Dump” mode Check of extraction timing with extracted beam Commission extraction line BDI –BTV (SE, D, DD), BPM (SE, D), BLMs, BCTs Any major problems will be apparent at this stage!

5. 18 July 20075 Before first pilot ramp…ii Extracted beam: 1 pilot @ 450 GeV (inject & dump) Verification of extraction trajectory and aperture –Vary orbit in IR6 and measure aperture at TCDS/MSD/TD line –Optimise extraction trajectory (orbit, MKD, MSD); define ‘reference’ (UA access for MKD trim!) Opening for extracted beam (H plane) at TCDS and MSD MKD sweep { Extracted beam aperture vs IR6 orbit

6. 18 July 20076 Extracted beam: 1 pilot @ 450 GeV (inject & dump) Logging and fixed displays –Checks that the beam related data is being correctly acquired and displayed XPOC basic functionality (trajectory, BLMs, BCT, kickers, BTVDD, …) –Check that XPOC validation is working correctly for pilot setup Issue: safe change of configuration when changing beam. With MCS/SIS/sequencer? BDI Post-Mortem data –Check that all beam-dependant transient signals from the LBDS systems are being PM’d Before first pilot ramp…iii

7. 18 July 20077 Before first pilot ramp…iv Extracted beam: 1 pilot @ 450 GeV (inject & dump) 89  s MKD kicker waveforms (current signal) BTVDD ‘screenshot’ bunch 1300 MKB sweep measurements Important for MKB and TD line aperture BPMD and BTVDD. inject & dump, vary injected bunch bucket (≈10 meas. points) MKD kick waveform measurements Important for aperture at TCDS/MSD BPMD, BTVDD and BLMs. inject & dump, vary injected bunch bucket (5 meas. points)

8. 18 July 20078 During ramp with pilot… Extracted beam: 1 pilot @ 450-7000 GeV (dump in ramp) MKD, MKB kicker and MSD septum energy tracking –Extract single pilot at pre-defined energies in the ramp (calibrated points) – 1 TeV intervals. –Adjustment of kicker lookup tables means UA access –Time-consuming if done as dedicated measurement….need to organise in a quasi-parasitic way –Extraction with 2 pilots during the ramp is also needed to verify the abort gap timing…combine MKD lookup table calibration data

9. 18 July 20079 Before moving to unsafe beams…i Extracted beam: 2 pilots @ 450 GeV (inject & dump) MKD kicker “fine” timing adjustment Inject 2 pilots into positions 1 and 2808 (3.0  s spacing) Fine adjustment of MKD timing (IR6 synch BPMs and RF frequency) Acquire last turn of bunch 2808 in LHC to verify MKD kick (  0.5  or 3  rad) bunch 1 turn n 270  rad kick bunch 2808 turn n-1  3  rad kick Note: this also needs to be checked through the ramp… MKD kick waveform 3.0  s

10. 18 July 200710 Before moving to unsafe beams…ii Circulating beam: safe beam @ 450 GeV Abort gap “watchdog” –Fine timing between IR6 and injections needs to be adjusted with beam Abort gap monitoring and cleaning commissioning Interlock BPMs for IR6 maximum orbit –Interlocked to around ±3.6 mm. Threshold setting and tests SW interlock for beam position at TCDQ Beam stability with orbit feedback at TCDQ and MSD

11. 18 July 200711 Before moving to unsafe beams…TCDQ Circulating beam: 1 pilot @ 450 GeV Adjustment of TCDQ/TCS jaws to 450 GeV position (≈10  ) –Beam axis wrt jaw, adjustment of jaw tilt, movement cross-calibration –TCS – 2 jaws - more accurate movement - tighter setting (by ≈0.5  ) –Needs BLMs and collimator controls Orbit at TCDQ –Measurement of beam axis Check that LHC aperture is protected…… Circulating beam: safe beam @ 450-7000 GeV Establish TCDQ movement function during ramp –Interdependence with collimation system –Check of interlock functions and chain Circulating beam: safe beam @ 7 TeV Establish TCDQ movement function during squeeze Accurate adjustment of TCDQ and TCS jaws in final position –Establish reference settings for target  * during next phase of commissioning –Interdependence with collimation system  Interdependency on collimation settings, and on orbit feedback  Iterations (changes of orbit,  -beat,  *) to finalise TCDQ reference function

12. 18 July 200712 Before first 43b ramp… Extracted beam: 43b @ 450 GeV (inject, fill & dump?) –Start with 43 pilots, to keep below the damage threshold…..? –When this is OK, move to 43 bunches of 4  10 10 for validation Losses in extraction channel and along the dump line –Reduced sweep with staged MKB means generous TD aperture Check BDI response – new gains etc. maybe needed Logging, PM and XPOC validations –Establish new reference data for XPOC… Check abort gap monitoring and cleaning BTVDDBPMD

13. 18 July 200713 Before first 156b ramp… Extracted beam: 156b @ 450 GeV (inject, fill & dump?) As per 43b activities… Plus….. –Specific check of TDE thermal behaviour (nominal 10 kW load)? Could load with ≈4 kW with repeated inject, fill & dump of 156 bunches…

14. 18 July 200714 LBDS beam commissioning – pilot beam LBDS beam commissioning activityLHC modeBeam typeEnergy GeV Things to do before first pilot extraction IR6 optics measurementsInjectionCirculating 1 pilot450 Commission dedicated LBDS BDI in IR6InjectionCirculating 1 pilot450 Extraction element aperture measurementsInjectionCirculating 1 pilot450 … before first pilot ramp First extractions: rough timing adjustmentInject & dumpExtract 1 pilot450 TD line BDI commissioningInject & dumpExtract 1 pilot450 Extraction trajectory and aperture measurementsInject & dumpExtract 1 pilot450 Data diagnostics: IPOC, logging, FDs, PM, XPOCInject & dumpExtract 1 pilot450 MKD waveform overshoot measurementsInject & dumpExtract 1 pilot450 MKB sweep measurementsInject & dumpExtract 1 pilot450 … with the pilot ramp Energy tracking measurementsRampExtract 1 pilot450-7000 …before moving to operation with potentially “unsafe” beams Fine timing adjustmentInject & dumpExtract 2 pilots450 Commission SW interlock on beam position at TCDQInjectionCirculating, safe beam450 Commission IR6 orbit BPM interlockInjectionCirculating, safe beam450 Commission abort gap watchdogInjectionCirculating, safe beam450 TCDQ “injection setting” positioningInjectionCirculating, safe beam450 Fine timing in rampRampExtract 2 pilots450-7000 TCDQ positioning at 7 TeVAdjust/squeezeCirculating, 1 pilot7000

15. 18 July 200715 LBDS beam commissioning – 43b LBDS beam commissioning activityLHC modeBeam typeEnergy GeV Things to do before first 43b extraction Orbit feedback / stability checks at TCDQInjectionCirculating, 43b450 Abort gap monitor and cleaningInjectionCirculating, 43b450 … before first 43b ramp Extraction trajectory checksInject & dumpExtract 43 pilots450 TD line BDI checksInject & dumpExtract 43b450 Data diagnostics: XPOCInject & dumpExtract 43b450 TDE thermal behaviourInject & dumpExtract, 43b450 … with the 43b ramp Energy tracking and abort gap timing checksRampExtract 43b450-7000 … with 43b at 7 TeV TCDQ positioning at 7 TeVAdjust/squeezeCirculating, 43b7000

16. 18 July 200716 LBDS beam commissioning – 156b LBDS beam commissioning activityLHC modeBeam typeEnergy GeV Things to do before first 156b extraction Orbit feedback / stability checks at TCDQInjectionCirculating, 156b450 Abort gap monitor and cleaningInjectionCirculating, 156b450 … before first 156b ramp Extraction trajectory and BDI checksInject & dumpExtract, 156 pilots450 Extraction trajectory and BDI checksInject & dumpExtract, 156b450 Data diagnostics: XPOCInject & dumpExtract, 156b450 TDE thermal behaviourInject & dumpExtract, 156b450 … with the 156b ramp Energy tracking and abort gap timing checksInject & dumpExtract, 156b450-7000 …with 156b at 7 TeV TCDQ positioning at 7 TeVAdjust/squeezeCirculating, 156b7000 This is the same list of activities as from pilot to 43b. It will be essentially the same list for all major changes in LHC beam (filling pattern, significant intensity steps, optics, emittance, …) It will also be repeated in detail when the full MKB kicker system installed

17. 18 July 200717 Some issues/questions Presently difficult to make 1:1 mapping between full system commissioning, MP aspects commissioning and overall LHC commissioning…. –Inconsistencies and different assumptions –Incomplete stages –Do NOT want to write and maintain 3 separate sets of procedures!!! How do we assure that only the ‘authorised’ beam is used –Operational states and allowed LHC beam conditions – MCS, SIS and sequencer? Acceptance criteria need more explicit definition – but some of these are more ‘fuzzy’… –Will try to add these in the ‘test’ document