Transcript PRISM-II and Measurement of Muon Electric Dipole Moment

PRISM-II and Measurement of
Muon Electric Dipole Moment
based on J-PARC mu-edm LoI
NuFACT-J'03
M. Aoki
Osaka University
Contents
◆Muon electric dipole moment
◆Concept of the mu-edm measurement
◆PRISM-II
◆Muon storage ring
◆Experimental Site
◆Control of the systematics
◆Summary
Leptogenesis
CPV in CKM is not enough to explain Baryon Asymmetry
→ New sources of CPV beyond the SM
 Oscillation + CPV in lepton sector → leptogenesis
Fukugida & Yanagida ‘86
AND if SUSY exists → ・muon EDM
・T-violation in muon LFV
g-2 and mu-edm
◆General dipole moment, D
DNP  DNP e iCP
dNP
 aNP 
 3 1022
tan CP e  cm
9 
3 10 
SUSY with the Muon
-LFV
CPV
LFV diagram in SUSY-GUT
LFV diagram in SUSY-GUT
large top Yukawa coupling
large top Yukawa coupling
µ÷
mixing
~
µ÷
e÷
µ
LFV diagram in SUSY-GUT
mixing
~
e÷~

µ÷
e
µ
e
large top Yukawa coupling
mixing

µ
÷
B
÷
B
e÷~
e
÷
B
g-2
-EDM
LFV diagram in Standard Model
LFV diagram in Standard Model
LFV diagram in Standard Model
mixing in massive neutrinos
mixing in massive neutrinos
mixing in massive neutrinos
 -e conversion
 (m / mW )4
mixing

→eg

e
µ
26
 10
e
W

normal
mixing
 (m / mW )4
SUSY particles
mixing
squark
e

26
particles
 10
e
quark
µ
W
md








mb 
e
ms
µ
md˜




ex. K-decays, B-decays
lepton (neutrino)
m




e
m




m 


ex. neutrino oscillation


m˜s

m b˜ 
W 
slepton
 me2˜e˜

2
m˜ e˜
m 2

˜e̃
m 2˜e˜
m2˜ ˜
m2˜̃
m˜e2˜ 

m 2˜ ˜ 
m2˜˜  

ex. charged lepton LFV
 (m / mW )4
26
 10
e
g-2 and muon-EDM in SUSY
◆a(SM(DEHZ))-a(Exp) = (33.9±10.6)x1010
◆d < 10-20 e.cm
Concept of the experiment
◆Muon spin precession（相対）

 1
  E  E


e 
   aB   2  a
     B
m 
2 c
g 1  c



g2
g e
 e
,

,

2
2 2m
2 2mc
 第１項外部磁場によるmdmの回転
 第２項外部電場がローレンツ変換されてつくる磁場による
mdmの回転
 第３項edmの回転
a

◆第１項を第２項でキャンセルする
◆β×Bによる電場をつかう
◆キャンセル電場
 E=aBcβγ2 E=2 MeV/m、B=0.25 T
◆Edm電場
 E=Bcβ
B=0.25 T → E=72 MeV/m

 1
  E  E


e 
   aB   2  a
     B
m 
2 c
g 1  c




PRISM for mu-edm
◆Accelerate low energy muon upto
500 MeV/c
Initial muon
Decay survivability
Polarization
NP2 = 108 毎秒
~1011
~6%
~0.2?
◆一方、
d<10-24 e.cm → NP2>1016 total
20 - 500 MeV
PRISM
PRISM-2 for mu-edm
◆Accept 500 MeV/c muons and
phase rotate
Initial muon
Decay survivability
Polarization
NP2 = 109~1010 毎秒
~2×1010
~56%
~0.6
Transverse 800 p mm.mrad
Momentum acceptance ±30%
PRISM-2
PRISM-2 Muon decay channel
◆Curved solenoid
1T, r=45cm, R=5m
50deg curve
Transmission
 90% for 0.7 Gev/c1.1 GeV/c pion
800 p mm.mrad
350 MeV/c<p<650 MeV/c
PRISM-2 phase rotator
◆Use the 1st ring of
Japanese NF as PRISM2 phase rotator
0.3 - 1.0 GeV
Mu-edm storage ring
◆
◆
◆
◆
◆
◆
<R>=10 m
B=0.25 T, E=2 MeV/m
800 p mm.mrad
Δp/p=2%
Tune x=4.42, y=4.2
Beta function x=6.85 m, y=7.1 m
Experimental Site
Systematics
◆Non-planar (NP) systematics
E field at not in a median plane
Muon orbit is not in a median plane
◆How to control?
Inject muons into clockwise(CW) and
counter-clockwise(CC)
Benchmark with deuteron beam
◆edm = muon edm ×β

 1
  E  E


e 
   aB   2  a
     B
m 
2 c
g 1  c



◆Deutron NP = muon NP ×muon-γ2

E=aBcβγ2
Summary
◆d < 10-24 e.cm
→
NP2 > 1016/year
◆P(PRISM) > 0.3
◆N(PRISM) > 1012 @500 MeV/c
◆PRISM-2 ring (1st ring of the JNF)