Emittance measurement:• ID muons with time-of-flight• Measure x,y and t at TOF0, TOF1• Use momentum-dependent transfer

matrices iteratively to determine trace space at TOF0 & TOF1.

- measured pz & transfer matrix M(pz)

An extensive experimental program is planned for 2015, including data taken with variations on the original Step IV configuration.•No absorber: alignment & beam optics• Liquid H2 absorber (full/empty)

• Multiple scattering, Energy Loss g COOLING• Solid absorbers: LiH, Plastic, C, Al, Cu• LiH wedge absorber: emittance exchange

The MICE ExperimentAlain Blondel, DPNC, University of Geneva, on behalf of the MICE Collaboration

The MICE Method

MICE Ionization Cooling is the only practical solution to preparing ultra-high intensity muon beams for a neutrino factory or muon collider. The muon ionization cooling experiment (MICE) is under development at the Rutherford Appleton Laboratory (UK). STEP I The muon beam-line has been commissioned, and beams have been shown by direct measurement with the particle physics detectors to be adequate for cooling measurements, in rate, particle composition and emittance. STEP IV Measurements of beam cooling properties of liquid-hydrogen, lithium hydride and other absorbers are planned for 2014-2016. STEP VI A full cell of the ionization cooling channel, including RF re-acceleration, is under construction, aimed at operation by 2017-2019. The design offers opportunities for tests with various absorbers and optics configurations. Results will be compared with detailed simulations of cooling channel performance for a full understanding of the cooling process.

Summary

A schematic of the Step I MICE beam line

A schematic of MICE: the cooling channel & upstream and downstream detectors

Step IV: 2014-15

Fully engineered MICE Cooling Channel Cell Well… some ‘details’ left!

Step VI: 2017-19Major progress has been made recently in MICE with the successful commissioning of the beam line. First measurements of the m beam emittance have been made using the TOF detectors. Installation of all Step IV components will continue through 2014, followed by the first high precision (0.1%) emittance measurements made in MICE with the fiber trackers (470 mm space point resolution). Finally, world-wide effort continues on the construction of MICE Step VI with a goal of completion in 2018.

2. Reconstructed momentum pz for simulation (red), reconstructed simulation (blue) and data (black)

MICE m beam optics (en,pz)

Step I: Completed & Published

Everything works well!• Muon rate ~120 in 2ms spill @ 0.4Hz• TOF resolutions: st = 55, 53, and 50 ps and sx,y ~1 cm• First measurement of emittance made using TOFs.

All Step IV components nearing completion. By 2014, this engineering drawing will be replaced with a photograph!

Muon Storage Rings

Step I: Beam Measurements

1. Time-of-Flight (6,200) muon beam (P~0.6 D1)

'' 0

0

2221

1211

1

1

x

x

MM

MM

x

x

1

0

22

11

121

0

1

11'

'

x

x

M

M

Mx

x

MICE is a critical R&D experiment on the path toward neutrino factories and muon colliders. With the growing importance of neutrino physics and the discovery of a light Higgs (126 GeV), physics could be moving this way soon!

e

(mm

)

p (MeV/c)

Measure input particle x,x’,y,y’, t, t’=E/Pz

input emittance in

Measure output particle x,x’,y,y’, t, t’=E/Pz

output emittance outCOOLING CHANNEL

Measure parameters particle by particle: accumulate ~105 muons g D[(ein – eout/ein)] = 10-3

In such machines, the initial chain of capture, bunching, phase rotation, and cooling rely on complex beam dynamics and technology. Muon cooling g high intensity n factory, high luminosity m collider

Neutrino Factory

MICE recorded > 106 particle triggers with p, e, and m beams to meet Step 1 goals:• Calibrated detectors & understood beam• Generated reproducible m beams• Analysed beam composition, m rates, data

quality, and emittance• Took data for each e-p optics setting in

MICE

Time-of-flight (TOF) for 300 MeV/c p beam (D2=D1)

5. Transverse trace space for (6 mm, 200 MeV/c) m- beam. Non-linear effects at edges

Spectrometer Solenoid 2

Tracker 2

Challenges: high gradient (>8MV/m) RF cavities embedded in strong (>2T) solenoidal magnetic fields.

RFCC ModuleAbsorber

Spectrometer Solenoid & Tracker

RF Cavities Berkeley

RF Couplers - Berkeley

RF Amplifier: Daresbury

Be Windows

Absorber Windows

Mississippi

Berkeley

LH2 System

RAL

Focus Coil

UK

UK, US

Tracker 1Completed: Inner view shown

Diffuser UK

• TOF system allows excellent p, m, e separation up to 300 MeV/c

• CKOV for PID at momenta >250 MeV/c• KL (calorimeter) used to measure p and e

contamination in m beams

zx ppxx , zy ppyy ,

yy

M. Rayner, U Genève

DATA

MC

Preliminary

EMR: UGeneve

Trainingcomplete

Spectrometer Solenoid 1

US: Berkeley, DOE

3. Pion fraction in mbeam ~< 1% from KL

Coupling Coil – China-USCold and superconducting!