A T L A S A BI L I C E CMS PIC Coll PC RF C r y o LHC Vacuum S D B Magnets L L H QPS C b TOTEM LHC Overview & Status Click to edit subtitle style R. Alemany (CERN AB/ OP/LHC) WAO'07 R. Alemany (CERN Les Houches Seminar
C M S L Content H C b L H C A L I C E A T L A S ALICE 1. Accelerator complex Overall Strategy for 5. Commissioning: 2. Energy Stored in the HW Commissioning l Magnets Machine Checkout l ATLAS l Quench Protection Beam Commissioning l Stage A l System Stage B l l Power Interlock Stage C&D l System Documentation & Human 7. Resources l Energy Extraction LHCb Conclusions 8. CMS LHC R. Alemany (CERN AB/ OP/LHC) WAO'07
C M S L Accelerator complex for p H C b L H C A L I C E A T L A S CMS B2 Dump 5 RF LBDS 6 4 B1 Dump ollim (p) Collim (beta) 3 7 SPS 8 2 ALICE LHCb 1 TI2 TI8 8.7 T ATLAS T op energy(GeV) Circumference(m) 11.8 kA / 7 MJ PSB 1.9 K LINAC2 0.12 30 CPS 2 PSB 1.4 157 C A CPS 26 1232 cryodip. N R. Alemany (CERN AB/ 628 = 4 PSB I L OP/LHC) WAO'07 SPS 450
C M S L H C QRL (Cryogenic Line b L H C A L I C E Installation) A T L A S He inventory per sector LHC TDR R. Alemany (CERN AB/ + 1260 T LN2 per sector OP/LHC) WAO'07
C M S L LHC Dipoles Installation H C b L H C A L I C E A T L A S R. Alemany (CERN AB/ OP/LHC) WAO'07
C M S L H C Interconnecti b L H C A L I C E on A T L A S R. Alemany (CERN AB/ OP/LHC) WAO'07
C M S L Inner Triplet H C b L H C A L I C E A T L A S Inner Separation/ Matching Triplet Recombinati Quadrupoles on 4.5 K 1.9 K War 1.9 K LHC TDR m R. Alemany (CERN AB/ OP/LHC) WAO'07
C M S L LHC Arc H C b L H C A L I C E A T L A S 1.9 K LHC TDR MBB: Main Dipole MQ: Main Quadrupole MQT: T rim Quadrupole MQS: Skew Trim Quadrupole MO: Lattice Octupole MSCB: Sextupole (Skew Sextupole)+Orbit Corrector MCS: Spool Piece Sextupole MCDO: Spool Piece Octupole + Decapole (BPM: Beam Position Monitor) ~ 9000 magnets powered with ~1700 power converters R. Alemany (CERN AB/ OP/LHC) WAO'07
C M S L Contents H C b L H C A L I C E A T L A S ALICE 1. Accelerator complex Overall Strategy for 5. Commissioning: 2. Energy Stored in the HW Commissioning l Magnets Machine Checkout l ATLAS l Quench Protection Beam Commissioning l Stage A l System Stage B l l Energy Extraction Stage C&D l l Power Interlock Documentation & Human 7. Resources System LHCb Conclusions 8. CMS LHC R. Alemany (CERN AB/ OP/LHC) WAO'07
C M S Energy Stored in the L H C b L H C A L I C E Magnets A T L A S ALICE ~ 11 GJoule (only in the main dipoles*) corresponds to … … an aircraft carrier at battle- ATLAS speed of 55 km/h LHCb CMS the energy of ~3 T ons TNT the energy of 370 kg dark chocolate More important than the amount of energy is … LHC How fast (an safe) can this energy be released? R. Alemany (CERN AB/ OP/LHC) WAO'07 * 400 MJ in the main
C M S Energy Stored in the L H C b L H C A L I C E Magnets A T L A S ALICE If not fast and safe … ATLAS LHCb CMS LHC During magnet test campaign, the 7 MJ stored in one magnet were released into one spot of the coil (inter-turn short) R. Alemany (CERN AB/ P . Pugnat OP/LHC) WAO'07
C M Energy Stored in the S L H C b L H C A L Magnets: I C E A T L A S ALICE A Quench is the phase transition of a super-conducting l to a normal conducting state Quenches are initiated by an energy release of the l order of mJ: Movement of the superconductor by several � m ATLAS l (friction and heat dissipation) Beam losses: l l @7 TeV 0.6 J/cm3 can quench a dipole; this energy density can be generated by 107 LHCb protons CMS l @450 GeV (injection energy), ~ 109 protons are needed Failure in cooling l LHC R. Alemany (CERN AB/ OP/LHC) WAO'07
C M Energy Stored in the S L H C b L H C A L Magnets: I C E A T L A S ALICE To limit the temperature increase after a quench l The quench has to be detected ı Quench Detectors* l The energy is distributed in the magnet by force- l quenching the coils using Quench Heaters* ATLAS tio h n Sy nc ec Pr ot st m Que The stored energy is released in a controlled way l e Cold by-pass diodes* & Energy Extraction System The magnet current is switched off within << 1 l second Power Interlock System LHCb CMS Failure in QPS: l False quench detection: down time of some hours l Missed quench: damage of magnet, down time 30 l days LHC R. Alemany (CERN AB/ OP/LHC) WAO'07 * On every SC magnet
C M Energy Stored in the S L H C b L H C A L Magnets: I C E A T L A S LHC Main Dipole System in one sector Cold diode Quench Detectors ı V1-V2 ≠ 0 R Converter Power L 1 (SC Magnet) L 2 (SC Magnet) L 154 (SC Magnet) Switch Quench Heaters R (Energy Extraction) R. Alemany (CERN AB/ OP/LHC) WAO'07
C M S Magnet Energy: L H C b L H C A L I C E Energy Extraction System A T L A S • During normal operation ALICE every ramp down of the magnets implies energy extraction, but this takes ~20 min � case of a quench ATLAS • A dedicated Energy Extraction System for quench protection is needed • LHCb There are 32 EES for the CMS 24 13kA main circuits Switches (dipoles & quadrupoles) Resistors (+ the EES for the 600 A correctors) • LHC This system releases the energy in 104 s for the R. Alemany (CERN AB/ dipoles (-125 A/s) and in 40 s for the quadrupoles OP/LHC) WAO'07
C M S Magnet Energy: L H C b L H C A L I C E Power Interlock Controller A T L A S Power Converters ALICE • 36 PICs in LHC for the SC magnets QPS (warm magnets also have PICs) Cryo • 1 PIC per Powering Subsector UPS, AUG ATLAS LHCb CMS LHC If circulating beam R. Alemany (CERN AB/ OP/LHC) WAO'07
C M S L Contents H C b L H C A L I C E A T L A S ALICE 1. Accelerator complex Overall Strategy for 5. Commissioning: 2. Energy Stored in the HW Commissioning l Magnets Machine Checkout l ATLAS l Quench Protection Beam Commissioning l Stage A l System Stage B l l Power Interlock Stage C&D l System Documentation & Human 7. Resources l Energy Extraction LHCb Conclusions 8. CMS LHC R. Alemany (CERN AB/ OP/LHC) WAO'07
C M S Energy Stored in the L H C b L H C A L I C E Beams A T L A S ALICE ATLAS 25 ns Ebeam = Ep+ x Kb x Num p+/bunch Ep+ = 7 T eV Kb = 2808 LHCb CMS Nominal values Num p+/bunch = 1.15 x 1011 Ebeam = 362 MJules LHC Enough to melt 500 kg of R. Alemany (CERN AB/ copper OP/LHC) WAO'07
C M S L H Energy Stored in the Beams C b L H C A L I C E A T L A S ALICE LHC 10000.00 Increase with respect to existing accelerators : energy in • A factor 2 in magnetic field magnets • A factor 7 in beam energy 1000.00 Energy stored in the beam [MJ] • A factor 200 in stored energy LHC top energy ATLAS LHC injection 100.00 (12 SPS batches) Factor ~200 SPS fixed 10.00 ISR target HERA TEVATRON LHCb SPS batch to 1.00 LHC CMS RHIC proton 0.10 LEP2 SNS SPS ppbar LHC 0.01 1 10 100 1000 10000 R. Alemany (CERN AB/ Momentum [GeV/c] OP/LHC) WAO'07
C M S Energy Stored in the L H C b L H C A L I C E Beams: A T L A S ALICE Beam Dump Beam Dump Block Block (graphite) ATLAS H-V kicker for painting ~ 8 m the beam IR6 concrete LHCb Septum magnet shielding CMS deflecting the extracted beam 15 kicker magnets Is the only system in LHC able to LHC absorb the full nominal beam R. Alemany (CERN AB/ OP/LHC) WAO'07
C M Energy Stored in the S L H C b L H C A L Beams: I C E A T L A S Collimation System 56.0 mm ALICE 1 mm ATLAS +/- 6 = 3.0 mm Collimation System Functionality: Beam +/- 3 d 1. Absorb beam halo to avoid LHCb quenches CMS 2. Once beam losses appear they protect the equipment and E.g. Settings of collimators @7 T eV experiments. If BLMCs > LHC with luminosity optics Threshold � Beam R. Alemany (CERN AB/ Interlock Beam Dump Very tight settings � orbit OP/LHC) WAO'07 feedback!!
C M S Energy Stored in the Beams: L H C b L H C A L I C E Collimation System A T L A S ALICE ATLAS LHCb CMS LHC R. Alemany (CERN AB/ OP/LHC) WAO'07
C M S L Contents H C b L H C A L I C E A T L A S ALICE 1. Accelerator complex Overall Strategy for 5. Commissioning: 2. Energy Stored in the HW Commissioning l Magnets Machine Checkout l ATLAS l Quench Protection Beam Commissioning l Stage A l System Stage B l l Power Interlock Stage C&D l System Documentation & Human 7. Resources l Energy Extraction LHCb Conclusions 8. CMS LHC R. Alemany (CERN AB/ OP/LHC) WAO'07
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