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MICE M uon I onisation C ooling E xperiment. Paul Drumm Rutherford Appleton Laboratory 19 th May 2005. p + m + + n m. m + n e + n m + e +. The Neutrino Factory. Factor of 10 in performance. Decay. America. Europe. Asia. Ionisation Cooling. Benefits: Small apertures
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MICEMuon Ionisation Cooling Experiment Paul Drumm Rutherford Appleton Laboratory 19th May 2005
p+ m+ + nm m+ ne + nm + e+ The Neutrino Factory Factor of 10 in performance Decay America Europe Asia
Ionisation Cooling • Benefits: • Small apertures lower cost/higher performance • Challenges: • Must be fast (2.2 µs muon lifetime) • Must be safe & practical • Cooling: • …is 25% of the cost of a Neutrino Factory • …gives a factor of 10 in performance • …has never been done before • …has the challenge to combine liquid hydrogen, high-gradient RF power, and intense beams!
Cooling Channel strong focus long radiation lengthhydrogen Cooling Heating Small Emittance Large Emittance m m Beam Beam One Cooling Cell SC-Solenoid Cryogenic Absorber RF -Cavities
m Detectors SC-Solenoid Cryogenic Absorber RF -Cavities Diffuser MICE EU design study 44/88 MHz; US design study 201 MHz MICE Reproduces part of US “study II” channel: 201 MHz Bz • Proof of principle • Engineering • Safety • Performance
Focus Coils …MICE Calorimeter Cherenkov ToF Tracking Spectrometers Coupling Coils Beam Diffuser Matching Coils RFCavities Liquid Hydrogen Absorbers
Performance aims (No RF focusing in MICE) (figure from proposal) initial large emittance – cooling initial small emittance – heating Aim for a 10% cooling effect; measure eout/ein to an accuracy of 10-3
m m Step II m Step III m m Step IV Step V m Step VI 2009? Step I: Spring 2007 Study Systematically
The long road…(some history) THE MICE COLLABORATION 3 continents 7 countries 40 institute members 140 individual members - Engineers & physicists • 2001 birth of MICE • 2002 LoI to PSI & RAL • PSI:+ve but no, • RAL:yes requested a full proposal • Early 2003 proposal to RAL • IPR (Astbury) panel • MICE-UK: PPRP • Autumn 2003: CCLRC gave scientific approval based on recommendations of the IPRP & dependent on funding • End 2003 MICE-UK went to “Gateway” (G1) • Mid 2004; ok but reservations on international funding… • By late 2004: • Project costs & schedule reviewed • Phase 1of project submitted to the “Gateway” (G2&3) • Passed by PPARC science committee ( aware of Phase 2) • March 2005: MICE went through PPARC council; RCUK, and now (almost finally) CCLRC council • ministerial announcement; MICE funded April 2005 • 2005: Phase 1 approval & funds in place
MICE Phase 1 • Phase 1 builds: • The MICE muon beam line on ISIS/RAL • The tracking and particle ID systems needed to measure the performance of the cooling channel • Necessary R&D towards phase II • Phase 1 aims: • Characterisation of the muon beam • Firm foundation for building the full MICE channel assurance for the intl. funding agencies
Implementing MICE on ISIS ISIS: 50 Hz 800 MeV 300 µA MICE: 1 Hz 800 MeV ~0.1 µA
MICE Hall Nimrod linac hall HEP test beam MICE 1950’s equipment
An Overview • MICE Components: • Target & Muon Beam - Decay solenoid • Tracking Detector • Absorber Module • RF-Cavity Module & RF power • Infrastructure • cryo, pwr, ctrls, intlck, mech. • MICE web: • http://www.mice.iit.edu
Target Pion Capture Muon matching channel Decay Solenoid MICE Spectrometer Beam line design • production & capture • p Momentum selection • decay • m momentum selection • matching section • New target – “Straight-7” replaced • Reuse elements from HEP Test beam (quads and dipoles) • SC-solenoid from PSI • Matching elements found
Beam Line Elements • supercritical helium…
Schedule PHASE 2 PHASE 1 2004 shutdown work Key Milestone – Work During Shutdown Cryogenics Critical items Decay-Solenoid commissioning
Scintillating fibre tracking detector pattern recognition – systematic errors evaluated with cosmic rays – stringent tests in B field planned MICE tracker Spectrometer
Tracking Detector Cosmic tests Model forKEK test Performance achieved light output resolution
Absorbers & Hydrogen Safety Argon shroud & ventilation • 20 l each absorber • Explosive : 17% - 56% • Flammable : 4% - 75% • Ignition: 20mJ in air • Gas. Density: 6% of air • Liq. Density: 7% of water • Particular problem of pumping • Oxygen plates out on cold surfaces & cannot be detected • ISIS LH2 moderator is surrounded by vacuum & an outer He layer LH2 Vac-I O2 Un-detectable warm cold Vac-II O2 detectable In order for a hydrogen fire to occur, an adequate concentration of hydrogen, the presence of an ignition source and the right amount of oxidizer (like oxygen) must be present at the same time. But we know accidents happen! e.g. defrosting a blockage with a hot air blower!?
H2 absorber Ventilation duct Radiation shielding wall H2 Buffer Tank (1m3 approx) Vacuum jacket H2 Storage unit Hydrogen system layout: metal hydride storage! Venting turns out to be the most likely time for accidents Hydrogen storage tank H2 absorber H2 buffer tank
MICE Cryogenics • RAL/ISIS has no existing large cryogenic infrastructure • MICE baseline design based on a central cryo-plant • Expensive • as much as £2M! (TCF50~200W) • Analysis: heat all goes in transfer pipes! • A better way? • Cryocoolers = only a few watts at 4K!
Cryo-coolers as alternatives • Solid state + closed loop helium • Careful thermal design of magnets and absorber • Limit heat losses • Cool down times made practical by using initial charge of LN2 & LHe – Cryo-cooler then maintains against heat leaks & keeps temperature • 8 hours with pre-cool • Days without! • Decay solenoid – supercritical He - requires its own (small) refrigerator
201 MHz Cavity R&D MUCOOL R&D Curved Be windows 0.38 mm thick, 420 mm dia. 201 MHz
Emission in a magnetic field 805 MHz cavity in B field Enhanced field emission! Need to see at 201 MHz
Master Oscillator Controls etc Los Alamos CERN (4616) (116) HT Supplies 300 kW Amplifier 300 kW Amplifier 300 kW Amplifier 300 kW Amplifier 2 MW Amplifier 2 MW Amplifier 2 MW Amplifier 2 MW Amplifier HT Supplies LBNL RF Power Systemdependent on… 201 MHz Cavity Module 201 MHz Cavity Module
…refurbished RF kit TH 116 / TH170 UK Large devices! Baseline 8 MW – identified 4 × >2.5MW – subject to R&D LBNL
Remaining Phase I issues • Money • Shielding • Quads • Decay solenoid • Tracker Solenoid • Funding of Phase II! • Money • need to progress! Reuse of old equipment
m m Step II end 2007? m Step III m m Step IV Step V m Step VI 2009? Step I: Early 2007 MICE phase 1 MICE phase 2
Funding: How much do we need? • MICE phase 1 estimated at £13M • UK Contribution ~ £10M • Beam line+ • Contributions to tracker • Progress towards phase II • Significant International Contribution • Decay Solenoid+ • Tracker detector • Tracker solenoid
Funding Outlook • UK: funds for phase 1 • OST £7.5M (ink still wet!) • CCLRC (ASTeC ~£1.5M) • PPARC (~£1.5M) • Bid to PPARC for phase 2 (~£3M) • US: • Through MUCOOL ($1.4M/3 years+…) • Other bids in progress O($2M) • Spectrometer, Cavities, Coupling Coil, • Absorber windows • EU: • INFN bid to provide a spectrometer solenoid, detectors • Switzerland (solenoid), Belgium, Netherlands, Italy • important contributions to (pi) detector systems, DAQ • JP: • Tracker, KEK tests, absorber… Funding Limited - Build on synergies with MuCool program Situation not fully resolved beyond phase 1, but hopeful that MICE will run with a cavity module before end 2010
…Finally MICE is off to a good start… … lots to do… backed by an enthusiastic and confident collaboration… watch this space…