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Explore motivations, pros and cons, and impact of LHC sector test options towards efficient beam commissioning and system integration. Learn about test layouts and essential requirements for successful testing.
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Options for Possible Sector Test Mike Lamont
Outline • Motivation • Options • Space & Time • Access • Pre-requisites • Cold checkout • Impact • Schedule • Conclusions LHC sector test
Baseline • 1 week with beam • Pilot Beam for the most part: • single bunch of 5 - 10 x 109 protons • Total intensity: • 2 - 3 x 1013 protons LHC sector test
Motivation • Beam tests form a integral part of full beam commissioning • This has got to be done anyway • but gives lead time for problem resolution, improvements etc. • Beam: • Polarity of magnetic elements • Aperture in the cold machine • Response of key beam instrumentation • Magnet field quality • Very Visible Milestone LHC sector test
Integration • Full test of a majority of subsystems over more than one eighth of the ring • Allows staged approach to the full problem space • Time to fully resolve problems before the real thing • Analysis, improvements, resolution, adjustment • The lessons learnt will reduce the time needed for full commissioning Breathing space if there are any serious problem(less true now perhaps) LHC sector test
Integration & commission with beam: Full-blown system wide integration test LHC sector test
layout Option 1 LHC sector test
Option 1: Injection R8 – A78 – R7 • No temporary dump to be installed at IR7 - use collimators instead (3 primaries, 5 secondaries for the single beam). • No temporary installation of beam instrumentation at IR7. • Need small part of 8-1, all 7-8 hardware commissioned to 450 GeV+. Minimal Impact Solution LHC sector test
Option 1: Pros and Cons • Minimal requirements on Cryogenics & HWC • 2 sectors • Less area classified by RP • Less impact on other systems • BI, LBDS • Only one sector test - less systems tested • BI, LBDS, collimators missed • BI configuration not perfect • Rely on in situ instrumentation • Not ideal – no BCT – some implications for measurements LHC sector test
Option 2 LHC sector test
Option 2: Injection R8 – A78 – A67 – Dump • Use TCDQ and TCS to block down stream aperture – safeguard only - no installation of temporary dump. RP approval/study required • Beam onto TDE • Can use correctors to steer into dump channel - so should be able to guarantee very little beam goes onto TCDQ etc. • Rely on in situ instrumentation (BCT in dump line etc.). No temporary installation required. • Need small part of 8-1, all 7-8, all 6-7 hardware commissioned to 450 GeV+. LHC sector test
Option 2: Pros & Cons • Test beam dump and related systems • Don't irradiate ring - beam onto TDE (beam dump block) • Check IR7 optics, performance of warm magnets • Beam through 3 IRs, 2 full sectors • Full suite of Beam Instrumentation in place • FBCT, Screens, BLMs • Support required for 3 cold sectors cold while work in progress elsewhere in ring - clearly test has more of an impact. Favoured Solution LHC sector test
Option 3 – Injection point 2 • Outside possibility – would imply problems elsewhere • Need partial 1-2, complete 2-3 • Dump on collimators in IR3 LHC sector test
Tests LHC sector test
Access – closing the whole ring • Pre-preparation, DSO tests • 2 months • Closing the ring: patrols etc • 3-4 days • Experiments out for a week • “a disturbance but acceptable” • Access during test possible • to areas that don’t see beam • Supervised areas after test • Given analysis, and measurements during and after the test, it is envisaged that: • Certain areas might be declared controlled areas for the first few days after the test; • Thereafter these areas would join the rest of the sectors involved as supervised areas LHC sector test
Monitoring • Radiation monitoring • RAMSES operational • LHCb: 4-5 monitors planned under RAMSES • Beam Loss Monitors • Sensitive to losses at 1% level with pilot bunch intensity • Beam Intensities • Beam extracted, injected (and to dump) to be logged • RPG survey after the event and perhaps during the test to ensure that activation remains low. • Careful survey afterwards planned after the test near the injection dump and dump itself. LHC sector test
SPS Extr. Kicker BIC BIC BIC BIC BIC BIC BIC BIC BIC BIC BIC BIC BIC BIC BIC BIC 3/16 of LHC Beam Interlock System BIS • Radiation levels • BLM • Powering Interlock • Warm Magnet Interlock • Vacuum • LHCb Access system will provide input to BIS which will inhibit SPS extraction. Configurable if the case of extraction required & LHC not ready (e.g. extraction tests) SPS Extraction Lines Interlock System LHC sector test
Required circuits • Beam 2 Circuits only • For limited recycling, it would be preferable for listed circuits to be available to, say, the equivalent 1-2 TeV level.
Injection LHC sector test
Triplets & LHCb LHC sector test
LL5 & DS.L5 LHC sector test
A78 LHC sector test
MR4 LHC sector test
6-7 LHC sector test
Other systems • Injection elements: septa, kickers • Collimators • Machine Protection • Beam Instrumentation: • BPMs, BLMs, BTV, BCT, BST • Magnet Model • Controls • Software/tools • Access system • Radiation Protection • Radiation Monitoring • Optics, aperture model Test preparation largely orthogonal to HWC See Chamonix 2006 LHC sector test
Near test schedule LHC sector test
Injectors LHC sector test
Impact • Sector test makes clear demands on: • What is needed to be cold & commissioned and to what level • Fairly limited: Beam 2 Circuits & limited recycling,. • Cryogenics, QPS, HWC supportrequired during test • In general, low current levels with occasional cycles • Interesting possibility of quenches • Access • Experiments - “acceptable” • HWC – NB that commissioning in other sectors can continue • Scheduled access possible (could imagine access/day if we can guaranteed a reasonable efficient recovery). • LHCb LHC sector test
Conclusions • A sector test would be a useful exercise and undoubtedly speed full commissioning with beam • most of it has to be done anyway • Could provide a useful buffer if any major problems are discovered. • The impact is not negligible, mainly because the whole ring has to be closed • This in itself is a very useful exercise • Machine as is or as will be. Work carries on elsewhere. • All major installation will have finished and access to the zones affected after the test will be limited. • This is a back up - to be invoke if delays 3 months • Need minimum lead time of some weeks for preparation LHC sector test
Thanks… • Magnets Luca Bottura • Beam Instrumentation Rhodri Jones, Lars Jensen, Stephen Jackson • Injection Brennan Goddard, Jan Uythoven • Radiation Protection Doris Forkel-Wirth, Helmut Vincke • INB Ghislain Roy • Access Pierre Ninin • LHCb Rolf Linder • HWC Roberto Saban & team • Installation Katy Foraz • Planning Esther Barbero Soto • Vacuum Paul Cruikshank, Miguel Jimenez • Controls Robin Lauckner ++ • OP/AP Roger Bailey, Verena Kain, Massimo Giovannozzi, Stephane Fartoukh, Helmut Burkhardt, Alex Koshick, Stefano Raedelli, Ralph Assmann, Frank Zimmerman… and the rest of the commissioning team. LHC sector test
Chamonix 2006 LHC sector test
LHCb • Worst case scenario: it is estimated that a total 3 x 1011 protons will be lost in the LHCb region during the whole test. The losses will be distributed over time. It has to be noticed that this number is quite pessimistic – under “normal” beam conditions the losses are more in the order of 1x10-4. • The aperture in LHCb is large; the injection optics means relatively small beams in the inner triplet to the right of the experiment; the separation and crossing angle bumps will be off; there is therefore no reason to expect significant losses in this region. • RP conclusion (H. Vincke) • (Preliminary, based on extrapolations of presently available exemplary calculations): • Dose rates: • All 3 x 1011 protons will be lost in carbon surrounded by steel and copper (already existing calculation) at the last day of the 14 days of tests: maximum 13 uSv/h . • The 3 x 1011 protons will be lost in one point after one week. After the cooling time of another week the maximum dose rate will be 2.8 uSv/h. This scenario can be considered as a more realistic approximation of continuous losses (at the same loss point) over two weeks. • Assuming that the new French law on area classification will not become stricter than the present Swiss one: • Non-designated area: < 2.5 uSv/h for temporary stay (0.5 uSv/h for permanent working places, i.e. assuming 2000 hours/year) • This goal seems to be achievable, even under pessimistic assumptions. In case the dose rates will be higher (e.g. due to an incident), the area (around the loss point) will have to be classified as supervised area (radiation workers B in the worst case, but most probably VCT status (physicists and technicians from outside institutes will receive dosimeters without medical certificate) will be sufficient – to be checked). LHC sector test