lhc status and commissioning plans. lhc in 4 slides lest we forget progress to date present...

Download LHC status and commissioning plans. LHC in 4 slides Lest we forget Progress to date Present schedules Consequent plan for 2008

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  • Slide 1
  • LHC status and commissioning plans
  • Slide 2
  • LHC in 4 slides Lest we forget Progress to date Present schedules Consequent plan for 2008
  • Slide 3
  • R.Bailey, DESY, December 2007 LHC dipoles (1232 of them) operating at 1.9K 7TeV 8.33T 11850A 7MJ
  • Slide 4
  • R.Bailey, DESY, December 2007 And plenty more magnets besides Several thousand magnets Thousands of Interconnects Electrical Fluids Vacuum
  • Slide 5
  • R.Bailey, DESY, December 2007 And plenty of power circuits Several hundred Power Circuits
  • Slide 6
  • R.Bailey, DESY, December 2007 Lest we forget QRL Installation started in sector 7-8 in July 2003 Installation started in sector 7-8 in July 2003 Geometry, weld quality, procedures, leaks, support tables Geometry, weld quality, procedures, leaks, support tables Installation finished November 2006 (sector 78 by CERN) Installation finished November 2006 (sector 78 by CERN)
  • Slide 7
  • R.Bailey, DESY, December 2007 Lest we forget Main magnets First magnet installed March 2005 First magnet installed March 2005 Peak of ~1000 dipoles stored, allowed magnet sorting Peak of ~1000 dipoles stored, allowed magnet sorting Last dipole lowered April 26 th 2007 Last dipole lowered April 26 th 2007 Cryostating425 FTE. years Cryostating425 FTE. years Cold tests640 FTE. years Cold tests640 FTE. years Transport30000 km underground at 2 km/h! Transport30000 km underground at 2 km/h!
  • Slide 8
  • R.Bailey, DESY, December 2007 Lest we forget Triplets Heat exchanger problem During the pressure test of Sector 7-8 (25 November 2006) the corrugated heat exchanger tube in the inner triplet failed by buckling at 9 bar (external) differential pressure. During the pressure test of Sector 7-8 (25 November 2006) the corrugated heat exchanger tube in the inner triplet failed by buckling at 9 bar (external) differential pressure. The inner triplet was isolated and the pressure test of the whole octant was successfully carried out to the maximum pressure of 27.5 bar, thus allowing it to be later cooled down. The inner triplet was isolated and the pressure test of the whole octant was successfully carried out to the maximum pressure of 27.5 bar, thus allowing it to be later cooled down. Reduced-height of corrugations and annealing of copper near the brazed joint at the tube extremities accounted for the insufficient resistance to buckling. Reduced-height of corrugations and annealing of copper near the brazed joint at the tube extremities accounted for the insufficient resistance to buckling. New tubes were produced with higher wall thickness, no change in corrugation height at ends, and e-beam welded collars to increase distance to the brazed joint. New tubes were produced with higher wall thickness, no change in corrugation height at ends, and e-beam welded collars to increase distance to the brazed joint. Installation of these tubes was made in situ. Installation of these tubes was made in situ.
  • Slide 9
  • R.Bailey, DESY, December 2007 Lest we forget Triplets Supports problem Q1 supports at IP 5L On Tuesday March 27 2007 there was a serious failure in a high-pressure test at CERN of a Fermilab-built inner-triplet series of three quadrupole magnets
  • Slide 10
  • R.Bailey, DESY, December 2007 Lest we forget Triplets Supports solution Requirements for repair Requirements for repair Must be implemented in situ Must be implemented in situ Does not displace the fixed points of the assembly Does not displace the fixed points of the assembly React loads with sufficient stiffness to limit deflection at 150 kN design load React loads with sufficient stiffness to limit deflection at 150 kN design load Acts at any temperature between 300K and 2K Acts at any temperature between 300K and 2K To be implemented in Q1 and Q3 To be implemented in Q1 and Q3 Solution adopted Solution adopted Affixed at Q1 non-IP end and at Q3 IP end Affixed at Q1 non-IP end and at Q3 IP end Transfer load at all temperatures Transfer load at all temperatures Limits support deflections Limits support deflections Compound design with Invar rod and aluminium alloy tube Compound design with Invar rod and aluminium alloy tube Attached with brackets to cold mass and cryostat outer vessel Attached with brackets to cold mass and cryostat outer vessel Status Status All triplets repaired by September All triplets repaired by September Problem solved Problem solved
  • Slide 11
  • R.Bailey, DESY, December 2007 Commissioning of the power converters PC 18kV for the dipole circuits 400V for the others Water UPS for all converters above 4 kA DCCT Short Circuit UA, UJ, RR tunnel, UJ 1720/1720 installed Commissioning campaign on short circuit From mid 2006 to late 2007 100% commissioned
  • Slide 12
  • R.Bailey, DESY, December 2007 Machine commissioning without beam is by sector 8 distinct sectors for cryogenic and powering Picture today Order was originally determined by installation sequence 78 81 45 34 56 67 23 12
  • Slide 13
  • R.Bailey, DESY, December 2007 Shielded bellows on the cold interconnects (PiMs)
  • Slide 14
  • R.Bailey, DESY, December 2007 Plug in Module in equivalent cold position
  • Slide 15
  • R.Bailey, DESY, December 2007 RF mole Polycarbonate shell Diameter 34mm exterior 30mm interior Total weight ~15 g (ball 8g) RF characteristics 40MHz resonantcircuit Generates 20V between copper electrodes Battery powered Over 2hr lifetime Capacitive coupling to BPM electrodes 1V ~5mV -45db Coupling BPM trigger threshold at ~3mV
  • Slide 16
  • R.Bailey, DESY, December 2007 Commissioning of sector 45 (without triplet) Water in the oil of Compressor station Leak to insulating vacuum Stop for repair Leak to insulating vacuum Stop for repair Almost ready for powering
  • Slide 17
  • R.Bailey, DESY, December 2007 Beam tests October 2004 October 2007
  • Slide 18
  • R.Bailey, DESY, December 2007 Performance goals Nearly all the parameters are variable Nearly all the parameters are variable Number of particles per bunch Number of particles per bunch Number of bunches per beamk b Number of bunches per beamk b Relativistic factor (E/m 0 ) Relativistic factor (E/m 0 ) Normalised emittance n Normalised emittance n Beta function at the IP * Beta function at the IP * Crossing angle factorF Crossing angle factorF Full crossing angle c Full crossing angle c Bunch length z Bunch length z Transverse beam size at the IP * Transverse beam size at the IP * Thus, to achieve high luminosity, all one has to do is make (lots of) high population bunches of low emittance to collide at high frequency at locations where the beam optics provides as low values of the amplitude functions as possible. PDG 2005, chapter 25
  • Slide 19
  • R.Bailey, DESY, December 2007 Overall commissioning strategy for protons (est d. 2005) Hardware commissioning Machine checkout Beam commissioning 43 bunch operation 75ns ops 25ns ops I Install Phase II and MKB 25ns ops II Stage A BC No beamBeam D I.Pilot physics run First collisions First collisions 43 bunches, no crossing angle, no squeeze, moderate intensities 43 bunches, no crossing angle, no squeeze, moderate intensities Push performance Push performance Performance limit 10 32 cm -2 s -1 (event pileup) Performance limit 10 32 cm -2 s -1 (event pileup) II.75ns operation Establish multi-bunch operation, moderate intensities Establish multi-bunch operation, moderate intensities Relaxed machine parameters (squeeze and crossing angle) Relaxed machine parameters (squeeze and crossing angle) Push squeeze and crossing angle Push squeeze and crossing angle Performance limit 10 33 cm -2 s -1 (event pileup) Performance limit 10 33 cm -2 s -1 (event pileup) III.25ns operation I Nominal crossing angle Nominal crossing angle Push squeeze Push squeeze Increase intensity to 50% nominal Increase intensity to 50% nominal Performance limit 2 10 33 cm -2 s -1 Performance limit 2 10 33 cm -2 s -1 IV.25ns operation II Push towards nominal performance Push towards nominal performance
  • Slide 20
  • R.Bailey, DESY, December 2007 LHCb during Stage A Displace bunches in one ring (n on m) Displace bunches in one ring (n on m) 4 per SPS cycle in 43 bunch, 16 per SPS cycle in 156 bunch mode 4 per SPS cycle in 43 bunch, 16 per SPS cycle in 156 bunch mode Dedicated runs for LHCb (n on n) ? Dedicated runs for LHCb (n on n) ? Squeeze in point 8 (2m limit for bad LHC dipole polarity) Squeeze in point 8 (2m limit for bad LHC dipole polarity) All values for All values for nominal emittance nominal emittance 7TeV 7TeV Parameters Rates in 8 kbkbkbkbN * 8 (m)Luminosity (cm -2 s -1 ) Events/crossing 1 on 1 10 10 10 1.8 10 27