Transcript hitachi_0709 ver. memo

NEW APPROACH TO THE MUON g2
AND EDM EXPERIMENT AT J-PARC
Hiromi Iinuma (KEK) for
New g-2/EDM@J-PARC collaboration
1. Motivation and goal
2. Outline of new experiment
3. Summary
Motivation for Muon g-2 and EDM
a a
a
a
Exp-SM
11
a 
 255634910  3.2
Standard model
SM

QED

QCD

Weak

http://pdg.lbl.gov/2009/reviews/rpp2009-rev-g-2-muon-anom-mag-moment.pdf
Latest experimental result：
PRD73, 072003 (2006)
a
exp

a
2
 0.54 ppm
 0.1ppm
EDM upper limit:1.8 1019 e.cm
(95% C.L.)
PRD 80, 052008 (2009)
+++
++++
Recent theoretical work
HLMNT10(preliminary)
3.2 (Tau2010)
Scaling from electron EDM
EDM~1025 e.cm
A recent theoretical work
EDM = 1022~ 1024 e.cm ?
Electric Dipole
Moment




Go beyond at least order of
magnitude!  
G. Hiller et al. hep-ph/1008.5091v1 (2010, Aug.)
2010/9/28
How to measure a =(g2)/2 and EDM?
Measure the muon precession frequency in the uniform
magnetic field B




S
B

 
a  s  c
  e e  g  2  


B
a  sa c a  B 
m m
2 
 
a  a B


a
a
B
< 0.1 ppm
“Non-zero EDM case”
< 0.1 ppm


 
 2c
  
e
  a  EDM 
a  B  EDM   B
m

3
Measure two frequency vectors separately!!2010/9/28
Great E821 and beyond the horizon
Magic momentum + beam cancels focusing electric field term


   E

 
  E  2c
q    1
a  c  S  
a  B   2  a       EDM   B  
m 
c
  1
 c  



150 Statistics
(g-2) Cyclesuncertainty
in PositronTime
Spectrum!
• More muons!
<
0.1
29.3(0.46ppm)
EDM=0
magic ppm
PRD73,
072003
2/
=4.4sec
a
• For the better B/B <0.1ppm ( 0.17ppm);
(2006)
• Compact storage ring to reduce the field volume
• For thea
better
a/a <0.1 ppm ( 0.21ppm);

 0.54
ppm  0.46stat.  0.28syst. ppm
• Ultra-cold
muon
beam, even “off-magic” momentum
a
+
e detector
• High granularity
a
B
 0.17separately
ppm,
for
0.21
ppmand
• Measure two frequency vectors
g2
B
a
EDM measurements
Independent experimental approach provides independent
B=1.45
Tesla、diameter
14m、45m
round
systematic studies forEeven>clearer
physics
understanding!!
2010/9/28
4
1.8 GeV
calorimetry
e+ yoke pieces
12 magnet
High Intensity Muon Beam in JAPAN!
J-PARC
Thursday 10:00 Prof. N. Saito
KEK

P, 3GeV
-beam
Tokyo
Bird’s eye photo in Feb. 2008
5
2010/9/28
3 GeV proton beam
( 333 uA)
Graphite target (20 mm)
Surface muon beam
(28 MeV/c, 4x108/s)
Muonium Production
(300 K ~ 25 meV⇒2.3 keV/c)
Step1: Ultra-Cold + Source and LINAC
Proton beam
(3 GeV, 1MW, 25 Hz)
(28 MeV/c)
6
Laser
(2.3 keV/c)
Muon Linac
(300 MeV/c)
2010/9/28
3 GeV proton beam
( 333 uA)
Graphite target (20 mm)
Surface muon beam
(28 MeV/c, 4x108/s)
Muonium Production
(300 K ~ 25 meV⇒2.3 keV/c)
Super Precision Magnetic Field
(3T, ~1ppm local precision)
Step2: Injection & storage
+ beam
7
Step3: Detect decay e+
0.66 m diameter
=3 and B=3 [T]
(note: 14 m for E821)
2010/9/28
Expected precession signal from J-PARC
within a Snowmass year beam time !
Ee> 200MeV
Default 50% pol.
Study for high
pol. Is ongoing.
8
2010/9/28
Example EDM wiggle, if EDM=210-20 e.cm
example
 

EDM    B
Expected sensitivity for
EDM would be better than
210-20 e.cm
9
2010/9/28
R&D items are running!
Step1: Ultra-cold + source and LINAC
•
Test experiments to search the best
Mu production target are ongoing
at TRIUMF and RAL !
Hi Power Ly- Laser System R&D
LINAC R&D
•
•
Step2: Injection & storage
• See next few pages
Step3: Detect decay e+
•
•
10
Setup spin dependent
muon-decay including
EDM term in GEANT4
Positron detector design
• Hi-rate Si Tracker
• Belle sensor with SiLC
based FEE
2010/9/28
Back to Step2: Injection & storage
Technical difficulties:
 3T is too high to cancel fringe field by inflector,
 Required kick angle (~60 mrad) is too big.
3D-spiral injection

F
+

BR
Concept is simple
but real design ?
11
2010/9/28
Storage ring magnet (ver.0 design)
3T super conductive solenoid magnet
 Uniformity in the beam storage region<0.1ppm
 Careful design of fringe field for stable beam injection
Tunnel for + beam
Upper end cap (Iron)
Cylindrical
return yoke
(Iron)
Inner radius 1.6m
Super
Apply MRI
conductive
technology!
Main coils
1.8m
Pole tip (Iron)
Upper half
4.6m
12
1ppm level at storage
volume is achieved
2010/9/28
Storage ring magnet (ver.0 design)
1. 3 tesla super conductive solenoid magnet
2. Uniformity in the beam storage region<0.1ppm
3. Careful design of fringe field for stable+ beam injection

1.8m
Upper half
4.6m
13
+ beam orbit diameter 0.66m
2.1m round (cyclotron period=7.4 nsec)
2010/9/28
Beam acceptance study is ongoing
+
Start
y>0
ySolenoid axis
y<0
y<0
y>0
Beam acceptance
14
2010/9/28
Vertical kicker (ver.0)
Helmholtz type
Br(t)=Bpeak sin(t)
±10cm
STOP!
Coil
15
 Apply radial magnetic field to reduce
beam vertical momentum
 Prototype kicker is being designed for
test
2010/9/28
.
Summary
 A new muon g2 and EDM experiment at JPARC:
 Off-magic momentum
 Ultra-cold muon beam + compact g-2 ring
 Independent experimental approach provides independent
systematic uncertainty
 Complementary to New g2@FNAL
 Saturday 10:00 Prof. B. Lee Roberts
 http://gm2.fnal.gov/public_docs/proposals/Proposal_g-2-3.0Feb2009.pdf
 Active R&D efforts are ongoing!
 My next step: Verification test for injection + kicker system
16
2010/9/28
J-PARC g-2/EDM collaboration
 71 members (…still evolving)
 M. Aoki, P. Bakule, B. Bassalleck, G. Beer, A. Deshpande, S.
Eidelman, D. E. Fields, M. Finger, M. Finger Jr., Y. Fujirawa, S.
Hirota, H. Iinuma, M. Ikegami, K. Ishida, M. Iwasaki, T. Kakurai, T.
Kamitani, Y. Kamiya, N. Kawamura, S. Komamiya, K. Koseki, Y.
Kuno, O. Luchev, G. Marshall, M. Masuzawa, Y. Matsuda, T.
Matsuzaki, T. Mibe, K. Midorikawa, S. Mihara, Y.Miyake, J. Murata,
W.M. Morse, R. Muto, K. Nagamine, T. Naito, H. Nakayama, M.
Naruki, H. Nishiguchi, M. Nio, D. Nomura, H. Noumi, T. Ogawa, T.
Ogitsu, K. Ohishi, K. Oide, A. Olin, N. Saito, N.F. Saito, Y. Sakemi, K.
Sasaki, O. Sasaki, A. Sato, Y. Semeritzidis, K. Shimomura, B.
Shwartz, P. Strasser, R. Sugahara, K. Tanaka, N. Terunuma, D.
Tomono, T.Toshito, K. Ueno, V. Vrba, S. Wada, A. Yamamoto, K.
Yokoya, K. Yokoyama, Ma. Yoshida, M. H. Yoshida, and K.
Yoshimura
Thank you!
 18 Institutions
 Academy of Science, BNL, BINP, UC Riverside, Charles U., KEK,
NIRS, UNM, Osaka U., RCNP, STFC RAL, RIKEN, Rikkyo U., SUNYSB,
CRC Tohoku, U. Tokyo, TRIUMF, U. Victoria
 6 countries
 Czech, USA, Russia, Japan, UK, Canada
17
2010/9/28
Backups
18
2010/9/28
Requirements for Kicker
Br(t)=Bpeak sin(t)
=/Tkick
Field strength：
Bpeak = 1Gauss ~ 10 Gauss
Time distribution：
Tkick=150 nsec (c.f. 20 cyclotron periods)
Spatial distribution：
33cm±5mm in radial direction, 1% uniformity
±10cm in solenoid axis direction to reduce distortion o f
beam bunch shape
Minimal effect for positron detector：
1. Quench protection
2. Space problem
3. Eddy currents on cryostat wall
19
e+ detector
(Silicon tracker)
2010/9/28