550 likes | 691 Vues
CERN. C onseil E urop é en pour la R echerche N ucl é aire. E uropean C entre for N uclear R esearch. 20 Member States. Founded in 1954 Funded by the European Union. …most of the EU…. 8 Observer States and Organisations. 580 Institutes World Wide 2500 Staff
E N D
CERN Conseil Européen pour la Recherche Nucléaire European Centre for Nuclear Research 20 Member States Founded in 1954 Funded by the European Union …most of the EU… 8 Observer States and Organisations 580 Institutes World Wide 2500 Staff 8000 Visiting Scientists …Japan, Russia, USA… 35 Non-Member States …Australia, Canada, New Zealand… Pure Science – ParticlePhysics • Pushing the boundaries of research, physics beyond the standard model. • Advancing frontiers of technology. • Forming collaborations through science • Educating the scientists and engineers of tomorrow
We use the world’s largest and most complex scientific instruments to study the basic constituents of matter. These instruments are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions. Our flag-ship project is the Large Hadron Collider…
CERN CERN Accelerator Complex Lake Geneva Geneva Airport CERN LAB 2 (France) CERN LAB 1 (Switzerland)
CERN CERN Accelerator Complex Lake Geneva Large Hadron Collider (LHC) Geneva Airport CERN LAB 2 (France) Super Proton Synchrotron (SPS) Proton Synchrotron (PS) CERN LAB 1 (Switzerland)
CERN CERN Accelerator Complex Beam Dumping Systems Large Hadron Collider (LHC) ~ 9 km ~ 5.5 miles Beam-2 Transfer Line (TI8) Super Proton Synchrotron (SPS) Beam-1 Transfer Line (TI2) 150m underground, 100us for one turn, 1e12 protons / injection CERN, the LHC and Machine Protection
CERN CERN Accelerator Complex CMS LHC-b ALICE ATLAS
Why the LHC? material costs of the LHC and experiments ≈$4 billion The Higgs Boson Gravity is such a weak force – can it be explained? Dark Matter / Energy 96% of mass in the universe is unaccounted for Do Weakly Interacting Massive Particles (WIMPs) account for this? Beyond the Standard Model String Theory / Super Symmetry / Super String Theory / A Theory of Everything? We need some clues! high intensity = more ‘events’ high energy = more massive particles possible collide two beams… LHC Beam Intensity = 3 x 1014 p LHC Energy = 7 TeV [11]
Collisions [3]
Technological Challenges …To see the rarest events… LHC needs high luminosity of 1034 [cm-2s-1] 3 x 1014 p per beam … to get 7 TeV operation… LHC needs 8.3 Tesla dipole fields with circumference of 27 kms (16.5 miles) … to get 8.3 Tesla … LHC needs super-conducting magnets <2°K (-271°C) with an operational current of ≈13kA cooled in super fluid helium maintained in a vacuum Collisions generate PetaBytes of data Per year World’s largest machine 1 ppm two orders of magnitude higher than others 10x less pressure than on moon surface Stored energyper beam is 360 MJ Stored energy in the magnet circuits is 9 GJ A magnet will QUENCH with milliJoule deposited energy [11]
Technological Challenges Kinetic Energy of 200m Train at 155 km/h ≈ 360 MJ Stored energyper beam is 360 MJ Stored energy in the magnet circuits is 9 GJ [11]
Technological Challenges Kinetic Energy of 200m Train at 155 km/h ≈ 360 MJ Stored energyper beam is 360 MJ Stored energy in the magnet circuits is 9 GJ Kinetic Energy of Aircraft Carrier at 50 km/h ≈ 9 GJ [11]
Protection Function MagnetEnergy Emergency Discharge Powering Protection: 100x energy of TEVATRON 0.000005% of beam lost into a magnet = quench 0.005% beam lost into magnet = damage BeamEnergy Beam Dump Beam Protection: Failure in protection – complete loss of LHC is possible 10-20x energy per magnet of TEVATRON magnet quenched = hours downtime many magnets quenched= days downtime magnet damaged = $1 million, months downtime many magnets damaged = many millions, many months downtime (few spares)
Protection Function 100x energy of TEVATRON 0.000005% of beam lost into a magnet = quench 0.005% beam lost into magnet = damage BeamEnergy Beam Dump Beam Protection: Failure in protection – complete loss of LHC is possible Concrete Shielding Beam is ‘painted’ diameter 35cm 8m long absorber Graphite = 800°C
Protection Function 100x energy of TEVATRON 0.000005% of beam lost into a magnet = quench 0.005% beam lost into magnet = damage BeamEnergy Beam Dump Beam Protection: Failure in protection – complete loss of LHC is possible ≈ 400 µs over 27km To protect against fastest failure modes
LHC Equipment and Control System • Vacuum Example: • maintain correct pressure Plant Systems: Fulfill operational requirements Vacuum Pressure Vacuum Pump Speed Control [11]
LHC Equipment and Control System • Vacuum Example: • maintain correct pressure • bad pressure = close valves Vacuum Pressure Vacuum Valve Actuator Plant Protection: Ensure plant stays within limits Plant Systems: Fulfill operational requirements Vacuum Pressure Vacuum Pump Speed Control [11]
LHC Equipment and Control System Vacuum Pressure Vacuum Valve Actuator Plant Systems: Ensure plant stays within limits Fulfill operational requirements • Sensors, Actuators and Process maybecombined • No rules regarding combination • Must meet functionalrequirement Vacuum Pump Speed Control [11]
LHC Equipment and Control System Access doors Beam absorbers Personnel Safety System: People in perimeter – stop machine personnel safe but machine at risk • cannot be merged with plants • Must meet legal requirement [11]
LHC Equipment and Control System Machine Protection System: Prevent damage to machine Prevent undue stress to components • No rules regarding implementation • Must meet functionalrequirement [11]
LHC Equipment and Control System Machine Protection System: Prevent damage to machine Prevent undue stress to components • No rules regarding implementation • Must meet functionalrequirement powering protection closely coupled to powering plant [11]
LHC Equipment and Control System Personnel Safety System: Machine Protection System: danger exists – extract energy danger willexist – extract energy Plant Systems: [11]
LHC Equipment and Control System Personnel Safety System: Machine Protection System: danger exists – extract energy danger willexist – extract energy • Beam protection inputs from • Safety system • Plant systems • Dedicated sensors Plant Systems: [11]
Developing the Machine Protection System • Why am I here? … machine protection ≠ safety • But… • cost of protection system failure is enormous • LHC is (just) the first machine with these energy risks • High Energy Physics community has to learn to deal with the challenges • System-safety ideas, concepts and approaches have to be absorbed by CERN • LHC is its own prototype: • systems involved protection are unique • certain technologies used have never been tried on this scale before • I can argue that the MPS is fit for purpose • My mission: • rigorous development of machine protection as if it were a safety system • But: • can our argument-based approach be accepted by system-safety?
Developing the Machine Protection System • CERN’s machine protection system development process… • could this ever be considered as a safety-system? • prior knowledge • assumptions • simulations • failure cases • solutions for every failure case • testing • Implementation • verification It took more than ten years to address all of the issues for the LHC… And we’re still learning…
The Machine Protection System Today Powering Protection Beam Protection
The Story So Far 1994 2002 2005 2007 2008 2009 2010 2011 2012 2013 LEP CERN approves LHC project Decommissioning of theLEP machine
1994 2002 2005 2007 2008 2009 2010 2011 2012 2013 Install magnets LEP CERN approves LHC project preparation, installation, alignment and interconnection of magnets
1994 2002 2005 2007 2008 2009 2010 2011 2012 2013 Install magnets LEP CERN approves LHC project September 10th first circulating beam first circulating beam established in LHC
1994 2002 2005 2007 2008 2009 2010 2011 2012 2013 Install magnets LEP CERN approves LHC project September 10th first circulating beam September 18th first lesson learned Interconnection failure – damaged magnets and helium leak
Magnet Protection Magnet Interconnect
Ideal 13 kA Connection Scheme Superconducting Cable Tin – Silver Foils Cross Section View Longditudinal View – filled with Solder Superconducting Cable Copper Stabiliser
Incident location Dipole Bus bar
The Story So Far 3.5 TeV 7.0 TeV 1994 2002 2005 2007 2008 2009 2010 2011 2012 2013 Install magnets Repair Upgrade LEP November 30th 1.18 TeV CERN approves LHC project September 10th first circulating beam November 23rd 450 GeV September 18th first lesson learned November 20th second startup
The Future – Linear Accelerators CLIC – CompacyLInearCollider ILC – International Linear Collider LHC results = electron / positron collider required for detailed study CERN isdesigning CLIC machine protection Various Institutes designing ILC machine protection Only one of these likely to be built – depends on what LHC discovers • logical next step for physics • specification to be finished circa 2015 • > $10 Billion machines • 30-50 km long • beam energy densities 1000x higher than previous e-e+ machines • beam energy 10000x above component damage limit
Large Hadron Collider (LHC) Compact Linear Collider (CLIC)
The Future – ITER ITER – International Thermonuclear Experimental Reactor many synergies with LHC challenges CERN is consulting on the design of the ITER Machine Protection… • first steps of 50-year plan • prove / disprove fusion feasibility for commercialisation • > $10 Billion machine • > 100 GJ of stored magnetic energy • 500MW of fusion for 1000 seconds vs state-of-the-art: • 16MW of fusion for 1 second (Joint European Torus) Tritium – Deuterium Fusion [11]
The Future – ITER ITER – International Thermonuclear Experimental Reactor many synergies with LHC challenges CERN is consulting on the design of the ITER Machine Protection… • first steps of 50-year plan • prove / disprove fusion feasibility for commercialisation • > $10 Billion machine • > 100 GJ of stored magnetic energy • 500MW of fusion for 1000 seconds vs current record: • 16MW of fusion for 1 second (Joint European Torus) Tritium – Deuterium Fusion [11]
The Future – ITER ITER – International Thermonuclear Experimental Reactor Safety– prevent Tritium release Protection– protect the reactor Plant– protect the sub-systems [11]
The Future – ITER ITER – International Thermonuclear Experimental Reactor Safety– prevent Tritium release Protection– protect the reactor Plant– protect the sub-systems [11]