14 Cooldown of Sector 7-8From RT to 80K precooling with LN tons of LN2 (64 trucks of 20 tons). Three weeks for the first sector.From 80K to 4.2K. Cooldown with refrigerator. Three weeks for the first sector tons of material to be cooled.From 4.2K to 1.9K. Cold compressors at 15 mbar. Four days for the first sector.
15 Large helium refrigerator for cooling down to 4.5 K 33 50 K to 75 K K to 20 K g/s liquefaction600 kW precooling to 80 K with LN2 (up to ~5 tons/h)
21 Cool-Down until Saturday 14-7-7 Cool-Down Speed
22 Installation & equipment commissioning Procurement problems of remaining components (DFBs, collimators) now settledGood progress of installation and interconnection work, proceeding at high pace in tunnelNumerous non-conformities intercepted by QA program, but resulting in added work and timeTechnical solutions found for inner triplet problems and repair well underway.Commissioning of first sectors can proceed by isolating faulty triplets, but will have to be re-done with repaired triplets (needing additional warm-up/cooldown cycles)First sector cooled down to nominal temperature and operated with superfluid helium; teething problems with cold compressor operation have now been fixed. Second sector being cooled down.Power tests have started.
23 General scheduleEngineering run originally foreseen at end 2007 now precluded by delays in installation and equipment commissioning.450 GeV operation now part of normal setting up procedure for beam commissioning to high-energyGeneral schedule has been revised, accounting for inner triplet repairs and their impact on sector commissioningAll technical systems commissioned to 7 TeV operation, and machine closed April 2008Beam commissioning starts May 2008First collisions at 14 TeV c.m. July 2008Luminosity evolution will be dominated by our confidence in the machine protection system and by the ability of the detectors to absorb the rates.No provision in success-oriented schedule for major mishaps, e.g. additional warm-up/cooldown of sector
24 LHC General Schedule, 5 July 2007 Interconnection of the continuous cryostatLeak tests of the last sub-sectorsInner Triplets repairs & interconnectionsGlobal pressure test &ConsolidationFlushingCool-downWarm upPowering TestsGeneral schedule Baseline rev. 4.0
25 European Strategy Group (1/2) [Quotes from the official statement – July 14, 2006]Þ Consolidation and upgrade of injectorsÞ LHC upgrade and maximum performance injectors
26 European Strategy Group (2/2) [Quotes from the official statement – July 14, 2006]Þ R & D for LHC upgrade and n facilityÞ preparation for n facility
28 Upgrade procedure 1. Lack of reliability: Ageing accelerators (PS is 48 years old !) operating far beyond initial parametersÞ need for new accelerators designed for the needs of SLHC2. Main performance limitation:Excessive incoherent space chargetune spreads DQSC at injection in thePSB (50 MeV) and PS (1.4 GeV) becauseof the high required beam brightness N/e*.Þ need to increase the injection energy in the synchrotronsIncrease injection energy in the PSB from 50 to 160 MeV kineticIncrease injection energy in the SPS from 25 to 50 GeV kineticDesign the PS successor (PS2) with an acceptable space charge effect for the maximum beam envisaged for SLHC: => injection energy of 4 GeV
35 Direct benefits of the new linac Stage 1: Linac4 (3/3)Direct benefits of the new linacStop of Linac2:End of recurrent problems with Linac2 (vacuum leaks, etc.)End of use of obsolete RF triodes (hard to get + expensive)Higher performance:Space charge decreased by a factor of 2 in the PSB=> potential to double the beam brightness and fill the PS with the LHC beam in a single pulse,=> easier handling of high intensity. Potential to double the intensity per pulse.Low loss injection process (Charge exchange instead of betatron stacking)High flexibility for painting in the transverse and longitudinal planes (high speed chopper at 3 MeV in Linac4)First step towards the SPL:Linac4 will provide beam for commissioning LPSPL + PS2 without disturbing physics.Benefits for users of the PSBGood match between space charge limits at injection in the PSB and PS=> for LHC, no more long flat bottom at PS injection + shorter flat bottom at SPS injection: easier/ more reliable operation / potential for ultimate beam from the PSMore intensity per pulse available for PSB beam users (ISOLDE) – up to 2´More PSB cycles available for other uses than LHC
36 LPSPL and SPL beam characteristics 2 2’ CDR2 “LPSPL” for SPS & LHC Stage 2: LPSPL + PS2 (1/3)LPSPL and SPL beam characteristicsStage22’CDR2“LPSPL” for SPS & LHC“SPL”Energy (GeV)3.545Beam power (MW)0.194 - 8Rep. frequency (Hz)50Protons/pulse (x 1014)1.41.21Av. Pulse current (mA)4020Pulse duration (ms)0.571.90.4Bunch frequency (MHz)352.2Physical length (m)430~4605353 different designs:CDR2 (2006) based on 700 MHz high-gradient cavities“LPSPL” for LHC (2007) with low beam power, for the needs of the LHC“SPL” at higher energy, for the needs of neutrino production
37 PS2 beam characteristics PS2 PS Stage 2: LPSPL + PS2 (2/3)PS2 beam characteristicsPS2PSInjection energy kinetic (GeV)4.01.4Extraction energy kinetic (GeV)~ 5013/25Circumference (m)1346628Maximum intensity LHC (25ns) (p/b)4.0 x 10111.7 x 1011Maximum intensity for fixed target physics (p/p)1.2 x 10143.3 x 1014Maximum energy per beam pulse (kJ)100070Max ramp rate (T/s)1.52.2Repetition time at 50 GeV (s)~ 2.51.2/2.4Max. effective beam power (kW)40060
38 Direct benefits of the LPSPL + PS2 Stage 2: LPSPL + PS2 (3/3)Direct benefits of the LPSPL + PS2Stop of PSB and PS:End of recurrent problems (damaged magnets in the PS, etc.)End of maintenance of equipment with multiple layers of modificationsEnd of operation of old accelerators at their maximum capabilitySafer operation at higher proton flux (adequate shielding and collimation)Higher performance:Capability to deliver 2.2´ the ultimate beam for LHC to the SPS=> potential to prepare the SPS for supplying the beam required for the SLHC,Higher injection energy in the SPS + higher intensity and brightness=> easier handling of high intensity. Potential to increase the intensity per pulse.Benefits for users of the LPSPL and PS2More than 50 % of the LPSPL pulses will be available (not needed by PS2)=> New nuclear physics experiments – extension of ISOLDE (if no EURISOL)…Upgraded characteristics of the PS2 beam wrt the PS (energy and flux)Potential for a higher proton flux from the SPS
39 Upgrade the LPSPL into an SPL (multi- MW beam power at 2-5 GeV): Stage 2’: SPLUpgrade the LPSPL into an SPL (multi- MW beam power at 2-5 GeV):50 Hz rate with upgraded infrastructure (electricity, water, cryo-plants, …)40 mA beam current by doubling the number of klystrons in the superconducting partPossible usersEURISOL (2nd generation ISOL-type RIB facility)=> special deflection system(s) out of the SPL into a transfer line=> new experimental facility with capability to receive 5 MW beam power=> potential of supplying b-unstable isotopes to a b-beam facility…Neutrino factory=> energy upgrade to 5 GeV (+70 m of sc accelerating structures)=> 2 fixed energy rings for protons (accumulator & compressor)=> accelerator complex with target, m capture-cooling-acceleration (20-50 GeV) and storage
40 Planning … CDR 2 3 MeV test place ready Linac4 approval Start for PhysicsSPL & PS2 approval
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