V. Kain AB/OP1Chamonix XV What is required to safely fill the LHC? V.Kain AB/OP Input from: B.Goddard, M.Jonker, Y.Kadi, R.Losito, V.Mertens, B.Puccio, R.Schmidt, J.Wenninger, M.Zerlauth Contents: Systems concerned When do we need injection protection? Issues affecting the commissioning strategy Systems required for different commissioning stages Conclusions

V. Kain AB/OP2Chamonix XV Systems concerned (1) Injection Protection starts in the SPS… …and ends after the first turn in the LHC. SPS-ExtractionTransferLHC-Injection MKIMKE

V. Kain AB/OP3Chamonix XV Systems concerned (2) Passive protection: TCDI Transfer Line Collimators (TCDI) to protect against upstream failures –full phase space coverage with 3 collimators (6 jaws) per plane, setting 4.5  –protects LHC at 7.5  7 collimators per line (momentum TCDI at start) 6 betatron collimators in last 300 m –TCDIs need beam for setting-up –TCDI beam commissioning needs LHC beam permit Sector Test/LHC ready TED TDI MKEMKI TCDIMOM TCDIH/V SPSTT40/60TI 8/2LHC phase space coverage with TCDI Ratio of seeds

V. Kain AB/OP4Chamonix XV Systems concerned (3) Passive Protection: TDI-TCDD-TCLI 4.25 m long TDI, mask TCDD and auxiliary collimators TCLI to protect against MKI failures –setting for TDI-TCLI 6.8  to protect LHC at 7.5  –need beam for setting-up

V. Kain AB/OP5Chamonix XV Systems concerned (4) Active Protection Active protection to guarantee –correct settings for SPS extraction, transfer lines and LHC injection via surveillance, e.g. magnet currents with ROCS surveillance and Fast Magnet Current Change Monitor collimator positions beam position in SPS extraction region SPS extraction septum girder position kicker charging voltage –high intensity beam can only be injected when beam is circulating in the LHC SPS safe beam intensity flag beam presence via the LHC safe parameters Equipment surveillance is User Inputs to the Beam Interlock System via Beam Interlock Controllers –additional input: SPS safe beam intensity, LHC beam presence, LHC energy

V. Kain AB/OP6Chamonix XV Systems concerned (5) Interlocking

V. Kain AB/OP7Chamonix XV Systems concerned (6) Software Software interlocking system (SIS) Trajectories, screen positions, MCS, maximum allowed injection intensity … Management of Critical Settings (MCS) Remote management of interlock settings in a secure way (needs SIS) MKI, MKE, TDI, TCLI, TCDI, ROCS, BLMs, BPCE, MSE First version for extraction/transfer tests Single client. Extraction/transfer/injection data analysis and diagnostics Shot-by-shot beam quality check to allow next extraction/injection Analysis after abnormal situation e.g. interlock (post mortem) First versions planned for CNGS commissioning/Sector Test. LHC injection sequencer setting-up of TDI/TCDD/TCLI inject & dump

V. Kain AB/OP8Chamonix XV When should we have “injection protection”? Formal tests and acceptance needed before beam is authorised. New territory for lots of hardware, software and procedures… Definition of setting-up procedures for passive protection devices still required. Different possible methods need testing with beam. Requirements for injection protection defined by damage level, but quench level 2-3 orders of magnitude below damage level –properly working injection protection also prevents quenches → improves operational efficiency during commissioning Should aim at making injection protection system fully operational as early as possible

V. Kain AB/OP9Chamonix XV When do we need “injection protection”? Injection protection MUST be in place AND working correctly when injected intensity exceeds damage limit Damage limit is ~ 2 · protons injected intensity (~ 5 % of nominal full batch) According to “overall commissioning strategy for protons”: –mandatory from commissioning stage II (936 bunches per ring, 24 · 4 bunches maximum injected, maximum intensity per bunch: 9 · protons) –should be operational for 156 on 156 with 9 · protons per bunch in stage I –to be commissioned during 43 on 43 to “authorise” the move to 156 bunches exception: TCLIs enhance performance of TDI –TCLIs are needed above 50% of nominal injected intensity and can be commissioned later Some earlier milestones –SPS extraction: CNGS high intensity commissioning 2006 –TI 8: high(er) intensity test 2006 (?) –Sector Test: procedure checks

V. Kain AB/OP10Chamonix XV Issues affecting commissioning strategy Passive Protection (1) Transfer line collimators –Setting-up procedures still need to be defined centering, alignment, beam size measurement; for single pass tight tolerance (~0.3 mm), small aperture (± 11 mm for MBI) –Possible single-pass method for alignment already tested in TI 8 commissioning 2004: use BCTs and non-local BLMs –TI 8 tests and Sector Test 2006: full method evaluation planned, see talk B. Goddard “Sector Test – Beam Tests” Promising results of method test during TI 8 commissioning. Tilt variations of 300  m had clear effect on transmitted intensity (b 0 to b 3 ).

V. Kain AB/OP11Chamonix XV Issues affecting commissioning strategy Passive Protection (2) To some extent injection protection can be tested independently of LHC…but: –Transfer line collimators (downstream of TED) possibly need BCT in IR4 for setting-up – Inject & Dump LHC Mode needs whole LHC ready inject & dump mode working (sequencer, timing, BIS,…) –currently being worked out beam dump commissioned

V. Kain AB/OP12Chamonix XV RR88 TI8 Issues affecting commissioning strategy Passive Protection (3) Can beam loss at the TCDI lead to LHC quenches? –during nominal operation –during setting-up (beam is scraped completely, not just tails) –during accidental loss of a full batch on one collimator jaw Preliminary results of FLUKA simulations: even for accidental losses of full batch LHC magnets do NOT quench (assuming 38 mJ/cm 3 quench limit). FLUKA model of 70 m transfer line TI 8 and adjacent LHC. S. Beavan, Y. Kadi Coil: max. 8 mJ/cm 3 TCDIV MB.A9R8 TI 8 LHC

V. Kain AB/OP13Chamonix XV Issues affecting commissioning strategy Passive Protection (4) TDI –Setting-up on circulating beam or injected beam? –Setting-up test on injected beam planned for Sector Test –Halo load? Do we need the TCLIs earlier? see talk “Critical beam losses during commissioning and initial operation” by G.Robert-Demolaize –rely on reproducibility (so far) need local orbit feed-back for setting-up (available when?) data from Sector Test eagerly awaited –TDI fixed in horizontal plane!!!!! enough aperture for non-injected beam? TCLIA –TCLI collimator close to D1 (common pipe) –must be set up for both beams –special setting-up procedures Vertical and horizontal alignment? –Beam1/beam 2 losses (crosstalk)

V. Kain AB/OP14Chamonix XV Issues affecting commissioning strategy Passive Protection (5) Collimator Control System –not clear when this will be available –need rudimentary version already for TI 8 tests and Sector Test (TCDI, TDI) –“Management of Critical Settings” (MCS) absolute or normalised interlock settings? orbit locally folded into setting for TDI/TCLI? –automatic procedures for setting-up (at a later stage: 43 on 43)? will certainly try to reuse as much as possible what the collimation project develops for LHC collimators

V. Kain AB/OP15Chamonix XV Issues affecting commissioning strategy Active Protection Interdependencies: e.g. for testing interlocking functionality of parts of surveillance equipment, need MCS and hence SIS available. Fast Magnet Current Change Monitor (FMCM) –device needed to detect fast current changes (about 15 families) –install 3 devices for CNGS commissioning – not all available –No high intensity commissioning of TI 8, if FMCM not ready? Interlock on the SPS energy is needed –TCDI protection level depends on  p (dispersion at collimator locations). Safe beam intensity –need to define value –10 12 protons? Factor 2 margin for NOMINAL emittance.

V. Kain AB/OP16Chamonix XV Timeline: Systems required for different commissioning stages installed & prototype test needed, but may not be fully available installed & fully operational beam 1 beam

V. Kain AB/OP17Chamonix XV Discussion Testing procedures and criteria have to be defined to declare systems commissioned after each commissioning stage –e.g. ready for pilot, ready for 43 on 43, ready for 156 on 156 and so on Issue: how and where to represent, store and “move” between the allowed operating conditions? E.g. number of bunches, I max,  min –Could use MCS + SIS (+sequencer)?

V. Kain AB/OP18Chamonix XV Conclusions Injection protection must be fully operational for 156 on 156 in commissioning stage I –commissioning should start at latest at 43 on 43 in stage I Main unresolved issues –Machine Protection LHC state control sequencer interplay between sequencer, MCS, SIS formalisation of commissioning pathway –Passive protection systems setting-up methods LHC reproducibility collimator control system A lot of important tests of the injection protection system and procedures can/will be done during the TI 8 tests and the sector test if we have TCDIs, MCS, injection post mortem, collimator control system, injection sequencer for setting-up the TDI, safe beam intensity flag from the SPS, …