The MICE collaboration

1
International Muon Ionization Cooling Experiment

• Why MICE?
• 2. Measurement
• 3. Prototyping
• 4. MICE at RAL
• 5. schedule

2
Why MICE?
Based on Muon collider ideas and development
(Palmer et al, 92-gt), the Neutrino Factory
concept (Geer, 1998) resonated in 1998 with the
final demonstration of Atmospheric Neutrino
Oscillations by the SuperK Collaboration.
International workshops NUFACT 99 (Lyon,
France) NUFACT 00 (Montery, California) NUFACT
01 (Tsukuba, Japan) NUFACT 02 (London, UK) NUFACT
03 (Columbia,NY,USA) NUFACT 04 (Osaka,
Japan) NUFACT 05 (italy?)
? Neutrino Factory is the ultimate tool for study
of Neutrino Oscillations -- unique source of
high energy ne --reach/sensitivity better by
order(s) of magnitude wrt other techniques
(e.g. super-beams) for
_
m ? e ne nm
q13 matter effects leptonic CP
violation ne ? nm and nt
NB leptonic CP violation is a key ingredient
in the leading explanations for the mystery of
the baryon-antibaryon asymmetry in our universe
3
Where will this get us
X 5
0.10
130
2.50
50
10
Mezzetto
comparison of reach in the oscillations right
to left present limit from the CHOOZ experiment,
expected sensitivity from the MINOS experiment,
CNGS (OPERAICARUS) 0.75 MW JHF to super
Kamiokande with an off-axis narrow-band beam,
Superbeam 4 MW CERN-SPL to a 400 kt water
Cerenkov_at_ Fréjus (J-PARC phase II
similar) Neutrino Factory with 40 kton large
magnetic detector.
4
3 sigma sensitivity of various options
NUFACT Superbeam only Beta-beam only Betabeam
superbeam Upgrade 400kton-gt 1
Mton
J-PARC HK 540 kton?
5
Neutrino Factory studies and RD
USA, Europe, Japan have each their scheme. Only
one has been costed, US study II
detector MINOS 10 about 300 M or M
Neutrino Factory CAN be done..but it is too
expensive as is. Aim ascertain challenges can
be met cut cost in half.
6

• Particle physicist
• Q Can a Neutrino Factory be built?
• Accelerator physisicst
• A YES! (US study II, CERN)
• but it is expensive,
• and many ingredients
• have never been demonstrated!
• ? RD is needed. (est. 5yrs)
• to
• reduce cost and
• ascertain performance
• among critical items

Cooling component development programme MUCOOL
collabration (US-Japan-UK)
7
IONIZATION COOLING

• A delicate technology and integration problem
• Need to build a realistic prototype and verify
  that it works (i.e. cools a beam)
• Difficulties lay in particular in
• operating RF cavities in Mag. Field,
• interface with SC magnets and LH2 absorbers
• What performance can one get?

Difficulty affordable prototype of cooling
section only cools beam by 10, while standard
emittance measurements barely achieve this
precision. Solution measure the beam
particle-by-particle
?RF Noise!!
state-of-the-art particle physics instrumentation
will test state-of-the-art accelerator
technology.
8
ECFA recommendations (September 2001)
MUTAC ( 14-15 jan 2003)(US) The committee
remains convinced that this experiment, which is
absolutely required to validate the concept of
ionization cooling, and the RD leading to it
should be the highest priority of the muon
collaboration. Planning and design for the
experiment have advanced dramatically() EMCOG
(6 feb 2003) (Europe) ()EMCOG was impressed by
the quality of the experiment, which has been
well studied, is well organized and well
structured. The issue of ionization cooling is
critical and this justifies the important effort
that the experiment represents. EMCOG recommends
very strongly a timely realization of MICE.
MUTAC Muon Technical Advisory Committee (Helen
Edwards, et al) (US) EMCOG European Muon
Coordination and Oversight Group (C. Wyss et al)
9
MICE is part of a international concerted effort
of RD towards a Neutrino Factory. It is one of
the four priorities set up by EMCOG European
Muon Coordination and Oversight Group -- High
intensity proton driver -- High power target --
high rep rate collection system (horns,
solenoid) -- Ionization coolng demonstration
These will correspond to the workpackages of
the ECFA/ESGARD superbeam/neutrino
factory feasibility study ? (package for
detector RD will be added!)
The contribution of experimenters in MICE is
justified and necessary given the difficulty of
the measurement. In addition it fulfills the ECFA
recommendation to increase education in
accelerator physics, and builds a community of
people who would be able to understand and
operate the real system
10
Superbeam/neutrino Factory design study (sub 2004)
Neutrino factory The ultimate tool for neutrino
oscillations
SPL
HIPPI
Superbeam
EURISOL design study (sub 2004)
APEC design study (sub 2005)
Very large underground lab Water Cerenkov, Liq.Arg
Beta beam
EURISOL
SPL physics workshop 25-26 May 2004 at CERN
? CERN SPSC Cogne meeting sept. 2004
11


An International Muon Ionization Cooling
Experiment (MICE)  
Summary
The aims of the international Muon Ionization
Cooling Experiment are     To show that it is
possible to design, engineer and build a section
of cooling channel capable of giving the desired
performance for a Neutrino Factory To place
it in a muon beam and measure its performance in
a variety of modes of operation and beam
conditions. The MICE collaboration has
designed an experiment where a section of an
ionisation cooling channel is exposed to a muon
beam and reduces its transverse emittance by 10
for muon momenta between 140 and 240 MeV/c.
The beam never lies
The experiment has been called for, recommended
and APPROVED. conditional to proper funding
and support.
Under these same assumptions, ionization
cooling of muons will be demonstrated by 2008
12
10 cooling of 200 MeV/c muons requires 20 MV
of RF single particle measurements gt
measurement precision can be as good as D ( e
out/e in ) 10-3 never done before either.
Coupling Coils 12
Spectrometer solenoid 1
Matching coils 12
Spectrometer solenoid 2
Matching coils 12
Focus coils 1
Focus coils 2
Focus coils 3
m
Beam PID TOF 0 Cherenkov TOF 1
RF cavities 1
RF cavities 2
Downstream particle ID TOF 2 Cherenkov Calorimet
er
Diffusers 12
Liquid Hydrogen absorbers 1,2,3
Incoming muon beam
Trackers 1 2 measurement of emittance in and
out
13
Belgium Downstream Cherenkov
Netherlands Magnetic probes and measurement
INFN Spectrometer solenoid, TOF detectors,Calorimeter, Tracker, DAQ
France Magnetic measurements
Switzerland Beam Solenoid (PSI), Trackerpossibly spectrometer solenoid contribution
CERN Refurbished RF power sources (refurbished Cryogenics?)
UK Beam, Home and Infrastructure! Focus coils, Absorber, Tracker
Russia under discussions
Japan Absorbers tracker and possibly spectrometer solenoid contribution
USA RF cavities, coupling coil Absorbers tracker up-and downstream Cherenkov
Responsibilities as stated in proposal
(Hardware)
14
Quantities to be measured in a cooling experiment
cooling effect at nominal input emittance 10
Acceptance beam of 5cm and 120 mrad
rms
equilibrium emittance 2.5 mm.radian
curves for 23 MV, 3 full absorbers, particles on
crest
15
Emittance measurement
Each spectrometer measures 6 parameters per
particle x y t x dx/dz Px/Pz y
dy/dz Py/Pz t dt/dz E/Pz Determines,
for an ensemble (sample) of N particles, the
moments Averages ltxgt ltygt etc Second moments
variance(x) sx2 lt x2 - ltxgt2 gt etc
covariance(x) sxy lt x.y - ltxgtltygt gt
Covariance matrix
M
Getting at e.g. sxt is essentially
impossible with multiparticle bunch
measurements
Compare ein with eout
Evaluate emittance with
16
G4MICE simulation of Muon traversing MICE
17

• requirements on spectrometer system
• must be sure particles considered are muons
  throughout
• 1.a reject incoming e, p, p
• gt TOF 2 stations 10 m flight with 70
  ps resolution
• 1.b reject outgoing e gt Cerenkov
  Calorimeter
• 2. measure 6 particle parameters
• i.e. x,y,t, px/pz , py/pz , E/pz
• 3. measure widths and correlations
• resolution in all parameters must be better
  than 10 of width
• at equilibrium emittance (correction less than
  1)
• s2meas s2true s2res s2true 1 (sres/
  strue)2 (n.b. these are r.m.s.!)
• 4. robust against noise from RF cavities

gt
Statistical precision 105 muons ? D( e out/
ein ) 10-3 in 1 hour Systematics!!!!
18
tracking in a solenoid
B

• Baseline tracker
• 5 planes of scintillating fiber tracker
• with 3 double layers.
• passive detector fast
• good for RF noise
• Very small fibers needed to reduce MS
• Little light ? VLPC readout (D0 experience)

19
TRANSVERSE MOMENTUM RESOLUTION OK
RESULTS
Pz resolution degrades at low pt
resolution in E/Pz is much better behaved
measurement rms is 4 of beam rms
20
Tracker RD
The prototype
Sci-fi a prototype of 3 out of 5 stations (3
double planes each) Was bulit and tested at D0
test stand Analysis in progress.
A typical cosmic ray track
Fiber feed-throughs
21
MICE tracker back-up option TPC with GEM readout.
250 microns pads connected in 3 sets of strips
1st Prototype being built difficulties Long
time constant RF photons on the GEMs? RF noise?
22
RF test setup TPG in LinacIII at CERN
detector to RF tanks 30cm Detector back to RF
power supply 1m
L.V. power supply
H.V. power supply
GEM DETECTOR
23
Noise with RF no sign of effect on GEMS
Fe55
55Fe pulse height 300mV Noise 40mV!
Zoomed signal
signal
24
Backgrounds
real background reduced by factor L/X0(H2) .
L/X0(det) 0.07 0.0026
measured dark currents

• Extrapolation to MICE (201 MHz)
• scale rates as (area.energy) X 100
• and apply above reduction factor 2 10-4
• 4 104 Hz/cm2 _at_ 8 MV/m _at_805 MHz
• 0.8 kHz/cm2 per sci-fi
• 500 kHz/plane (gate is 20ns)
• ! within ? one order of magnitude !

Dark current backgrounds measured on a 805 MHz
cavity in magnetic field! with a 1mm
scintillating fiber at dO(1m)
25
RF cavity (800 MHz) at Fermilab being pushed
to its limits (35 MV/m) to study dark current
emission in magnetic field. Sees clear
enhancement due to B field. Various diagnostics
methods photographic paper, scintillating
fibers Microscope
------? BCT and solid state counters have
demonstrated this and allowed precise
measurements Real cavities will be equipped with
Be windows Which do not show sign of being pitted
contrary to Cu
26
Absorber/Coil Assembly
Absorber is interchangeable, can be repaired
or changed to solid absorber.
27
LH2 Window R D (IIT, NIU, ICAR)
Various shapes have been studied to --reduce
thickness -- increase strength
?-- Breaking point was measured!
Strain gages 20 points
Shape measurement at FNAL
Pressure tests at NIU
Photogrammetry 1000 points
28
Absorber II
Absorber body will be built at KEK 2 prototypes
have been built Third one according to
Safety-compliant design safety review 9-10 dec.
2003
29
RF module
MICE is foresen with 8 RF cavities Closed with Be
windows (increase gradient / MW RF power) 201
MHz First cavity prototyped Completion in 2004
RF power sources Will be assembled from
equipement refurbished from Berkeley, Los
Alamos, CERN, RAL. Needed 8 MW peak power ? 23 MV
acceleration Operation at LN2 foreseen to
increase Volts / MW
30
First cavity shells ? have been produced
Similarly to LiH2 absorber windows, the RF
windows will be bell shaped to minimize thickness
(800 MHz prototype -?
31
INSTALLATION OF MICE at RAL
32
Beam line will include a 5m long 5T solenoid from
PSI (CH)
33
Hall has been emptied and preparations to host
the experiment begun
Large amount of LiH2 from absorbers requires
efficient storage Suggested solution metallic
hydride
Ventilation duct
Radiation shielding wall
H2 Buffer Tank (1m3 approx)
Vacuum jacket
H2 Storage unit
34
m
-
STEP I spring 2006
STEP II summer 2006
STEP III winter 2007
STEP IV spring 2007
STEP V fall 2007
STEP VI 2008
35
November 2001 Letter of Intent (LOI) submitted
to PSI and RAL January 2002 Positive
statements from PSI
cannot host experiment, will collaborate (beam
solenoid) March 2002 LOI reviewed at RAL
June 2002 Review panel encouraged
submission of a proposal. January 2003
Proposal submitted to RAL February 2003 EMCOG
recommends timely realization of MICE May
2003 International Peer review Panel strongly
recommends October 2003 Director(CE) of RAL
approves experiment conditional to
gateways UK funding in the range of gt10
M December 9-10 Safety review to clear
hydrogen safety design principle All seems
very well! -- MICE found a home -- Host lab ans
UK community enthusiastic Next important
steps Funding has to be secured from the
international partners -- Japan OK -- US
request to NSF -gt decision early 2004 -- request
have or will be posted to CH, B, NL, Italy,
CEA New collaborators (esp. Accelerator
physicists) welcome! NEUTRINO COMMUNITY SHOULD
SUPPORT THIS LONG TERM EFFORT!
36
Time Line
If all goes well and funding is adequate, Muon
Ionization cooling will have been demonstrated
and measured precisely by 2008
LHC/J-PARC start-up
At that time MINOS and CNGS will have started
and mesured Dm132 more precisely J-Parc-SK will
be about to start (Q13 measurement) LHC will
be about to give results as well
It will be timely (and not too soon!) to have by
then a design for a neutrino factory ), knowing
the practical feasibility of ionization
cooling
) plans proposal of a Neutrino factory
feasibility study to EU (2004-2007)
US Study III (2005 onwards)