Goals and Status of MICE The International Muon Ionization Cooling Experiment

1. Goals and Status of MICEThe International Muon Ionization Cooling Experiment J.S. Graulich

2. Plan • Motivations • Muon Cooling • MICE Design and Challenges • MICE’s current status • Beam Line • Detectors • Simulation and Analysis Software • Preparing for the future • Conclusion J.S. Graulich

3. Motivations:Neutrino Physics • Fundamental questions raised by neutrinos • Do they conserve the lepton number? • Are they their own anti-particle ? • Do they have Majorana masses ? • Do their oscillations violate CP ? • Why n masses are so small ? • A strong need for precision measurements • Mixing angles, Mass differences, Mass Hierarchy, dCP • Requires a new generation of facilities • Among the options: Super beam, Beta beam and Neutrino factory • Neutrino factory is not the simplest offers the best potential: performance and flexibility See Boris Kayser’s talk: “Seeking CP violation in neutrino oscillation is now a worldwide goal.” J.S. Graulich

4. Motivation:The Neutrino Factory • High energy & intensity • Very well defined beam content (nm , ne) or (nm , ne) • Start to End Simulation existsIDS ! see A. Cervera • 3 essential R&D needed - High power Target - Muon Cooling- FFAGs Sensitivityto dCP The neutrino factory is the ultimate tool for precise neutrino studies CERN Scientific Policy Committee, March 2010

5. Muon Cooling • Large divergence >< efficient acceleration • Beam Cooling = Emittance reduction • What is emittance ? ≠ divergence • In the 2D case (oversimplified) a beam is defined by a set of xi(z) x’ = dx/dz = Px/P In the absence of dissipative forces, e is conserved ! J.S. Graulich

6. Ionization Cooling • How to reduce emittance ? -> Frictions • Standard techniques don’t work for muons • They need >> 2.2 ms • Two steps • Energy loss by ionization (dE/dX) • Forward re-acceleration by RF cavities Cooling is achieved only for low Z material ! Mult. Scat. < dE/dx -> Liquid Hydrogen J.S. Graulich

7. Cooling Cell • Easy in principle… • In practice, the emittance is so large that • Need to contain the beam • Not single pass -> iterations • Technical Challenges • An extended liquid Hydrogen cryogenic system • High gradient RF cavities in strong magnetic field • Large number of Superconducting coils strongly coupled to each other • That’s why we need R&D -> MICE J.S. Graulich

8. MICE • Muon Ionisation CoolingExperiment • Design, build and operate a realistic section of coolingchannel • Measure its performances (in different modes) J.S. Graulich

9. MICE Step By Step Commission beam line & detectors Preciselymeasure incomingemittance & compare trackers Preciselymeasure muon cooling Test sustainable cooling Ultimate MICE goal: operate full coolingchannel Complete ! (This talk) 2012 J.S. Graulich

10. MICE Status @ RAL • Rutherford Appleton Laboratory, UK • Brand new muon beam line • Obtained from ISIS (800 MeV proton Synchrotron) J.S. Graulich

11. MICE Beam Line • Design Specifications: • ~ 1 Spill / 2 seconds • ~ 3 ms Spill duration • 100 muons / Spill • Muon momentum between 140 to 240 MeV/c • pD2 = pD1/2 (backward muons) Q1-Q3 D1 D2 Q4-Q6 Q7-Q9 J.S. Graulich

12. The Beamline is Operational Pion Decay Solenoid (during installation) Mice Target System in ISIS D1 Q1-Q3 Upstream Pion Beam Line D2 Q7-Q9 Q4-Q6 DownstreamMuon Beam Line J.S. Graulich

13. The Target is pulsing ISIS cycle • Critical active part • Parasitic mode: no perturbation to ISIS Users • 80 g acceleration ! • Magnetic “gun” • 570 000 dips@ 0.4 Hz extraction injection 10 ms Positionreading target depth Stator Beam Loss MICE Ti Target inside the ISIS beam pipe Bearing WaterCooling Acq. Gate ~ 3 ms Ti Target

14. Instrumentation for Step 1 • All detectors for Step 1 are operationalTOF0 after the 2nd triplet • TOF1 after the 3rd triplet • TOF2 at the very end (will move) Luminosity Monitors 3 Time of Flight Stations Beam Profile Monitors Calorimeter Downstream Monitor (GVA1) 2 Cherenkovs

15. Detector Rates Detector Rates scale linearly with Beam Loss J.S. Graulich

16. All TOF installed TOF1 installed at RAL TOF Scintillator • Two crossed layers of scintillator slabs, 1” thick • Fast PMTs on both sides • Muon/pion/electron PID • Measure the RF phase when muon arrives • Magnetic shielding is crucial for TOF1/2

17. TOF Resolution J.S. Graulich

18. Particle Identification m- Very precise Time of Flight measurement between TOF0 and TOF1 Allows separation between Electrons / muons / pions / For all momentaup to 280 Mev/c p- e- Time of Flight (ns) J.S. Graulich

19. Selecting Backward Muons m We want a muon beam ! We tune the second dipole (D2) to select muons going backward (in C.M. frame) w.r.t. to the original pions’ direction Pm ≈ Pp / 2 p J.S. Graulich

20. Pure muon Beam Selecting backward muons Pions are not transported Electrons are depleted MICE has a muon beam ! ~ 30 muons/spill/ V.ms m- No morep- here e- Time of Flight (ns) J.S. Graulich

21. Simulation and Analysis Software: G4MICE • Based on GEANT 4 for the simulation • A deliverable by itself • Also used for beam transport optimization • In competition with G4Beamline • Reconstruction of events from both simulation and data • Calculate elaborated quantity like e • In particular: momentum G4BeamLine Transport G4Mice Simulation and Analysis Jean-Sébastien Graulich

22. J.S. Graulich

23. Data Phase Space and Momentum Reconstruction: Q789 scan runs Simulation Q789 = -30%

24. Data Phase Space and Momentum Reconstruction: Q789 scan runs Simulation Q789 = -20%

25. Data Phase Space and Momentum Reconstruction: Q789 scan runs Simulation Q789 = -10%

26. Step 1 Program: beam optics • 3 momenta 140, 200, 240 MeV/c • 3 input emittances 3, 6 10 pmrad • A lot of data on tape • Next run in June 2011 J.S. Graulich

27. Next Step: Spectrometer Construction problems with the superconducting solenoids Tracker Ready, tested with cosmics, meet resolution specs Installation scheduled for 2012

28. Absorbers - FC • Each Absorber contains 20 L of Hydrogen • Produced at KEK, Japan • Thin Aluminum widows, all doubled for safety • The module integrates the absorber with the superconduction focus coil in production at Tesla • Integration to Step IV in 2012 1st absorber complete at Mirapro Jean-Sébastien Graulich

29. RFCC Module • Each module contains 4 RF cavities and a superconducting coupling coil • Water cooled copper cavities, 201 MHz • Each module compensates for 11-12 MeV energy loss in the absorbers • High Gradient (8 MV/m) in strong magnetic field (~4 Tesla) • Manufacturing in progress • Expected for 2013 Jean-Sébastien Graulich

30. Summary • The Neutrino factory is the best tool for future precise neutrino studies • MICE is exploring muon ionization cooling which is a key R&D toward the NF • MICE has completed its first step at RAL, UK • The muon beam and the detectors have been successfully commissioned • A particle by particle analysis has already been used to measure the beam emittance, using TOFs • The spectrometers and the first absorber will be installed in 2012 • MICE could be completed by 2013 J.S. Graulich

31. J.S. Graulich