Hiromi Iinuma (KEK) for New collaboration New collaboration 1. Motivation and goal 2. Outline of new experiment 3. Summary NEW APPROACH TO THE MUON g  2 AND EDM EXPERIMENT AT J-PARC

2 Motivation for Muon g-2 and EDM Latest experimental result ： PRD73, (2006) Standard model Recent theoretical work HLMNT10(preliminary) 3.2  (Tau2010) 2010/9/            Electric Dipole Moment  Scaling from electron EDM EDM~10  25 e.cm  A recent theoretical work EDM = 10  22 ~ 10  24 e.cm ? G. Hiller et al. hep-ph/ v1 (2010, Aug.) EDM upper limit:1.8  10  19 e.cm (95% C.L.) PRD 80, (2009) Go beyond at least order of magnitude!

How to measure a  =(g  2)/2 and EDM? Measure the muon precession frequency in the uniform magnetic field B 2010/9/28 3 < 0.1 ppm “Non-zero EDM case” Measure two frequency vectors separately!! B

Magic momentum  + beam cancels focusing electric field term B=1.45 Tesla 、 diameter 14m 、 45m round 12 magnet yoke pieces 4 EDM=0 Great E821 and beyond the horizon e+e+ 2  /  a =4.4  sec 150 (g-2) Cycles in Positron Time Spectrum! PRD73, (2006) E e+ > 1.8 GeV calorimetry 2010/9/28 More muons! Statistics uncertainty < 0.1 ppm (  0.46ppm) For the better  B/B <0.1ppm (  0.17ppm); Compact storage ring to reduce the field volume For the better  a /  a <0.1 ppm (  0.21ppm); Ultra-cold muon beam, even “off-magic” momentum High granularity detector Measure two frequency vectors separately for g  2 and EDM measurements Independent experimental approach provides independent systematic studies for even clearer physics understanding!!

High Intensity Muon Beam in JAPAN! 5 J-PARC Tokyo KEK 2010/9/28 Bird’s eye photo in Feb P, 30GeV  -beam P, 3GeV Thursday 10:00 Prof. N. Saito

6 Graphite target (20 mm) 3 GeV proton beam ( 333 uA) Surface muon beam (28 MeV/c, 4x10 8 /s) Muonium Production (300 K ~ 25 meV ⇒ 2.3 keV/c) 2010/9/28 Proton beam (3 GeV, 1MW, 25 Hz) Muon Linac (300 MeV/c) (28 MeV/c) Step1: Ultra-Cold  + Source and LINAC Laser (2.3 keV/c)

Graphite target (20 mm) 3 GeV proton beam ( 333 uA) Surface muon beam (28 MeV/c, 4x10 8 /s) Muonium Production (300 K ~ 25 meV ⇒ 2.3 keV/c) Super Precision Magnetic Field (3T, ~1ppm local precision) 2010/9/ m diameter  + beam  =3 and B=3 [T] Step2: Injection & storage Step3: Detect decay e + (note: 14 m for E821) 7

2010/9/28 8 Expected precession signal from J-PARC within a Snowmass year beam time ! E e > 200MeV Default 50% pol. Study for high pol. Is ongoing.

2010/9/28 Example EDM wiggle, if EDM=2  e.cm example 9 Expected sensitivity for EDM would be better than 2  e.cm

R&D items are running! 2010/9/28 10 Step2: Injection & storage Step3: Detect decay e + 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 Setup spin dependent muon-decay including EDM term in GEANT4 Positron detector design Hi-rate Si Tracker Belle sensor with SiLC based FEE See next few pages

3D-spiral injection ++ 2010/9/28 11 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. Concept is simple but real design ?

Storage ring magnet (ver.0 design) 2010/9/28 12 Cylindrical return yoke (Iron) Upper end cap (Iron) Pole tip (Iron) Tunnel for  + beam Upper half Super conductive Main coils 3T super conductive solenoid magnet  Uniformity in the beam storage region<0.1ppm  Careful design of fringe field for stable beam injection 1.8m 4.6m Inner radius 1.6m 1ppm level at storage volume is achieved Apply MRI technology!

Storage ring magnet (ver.0 design) 2010/9/28 13 ++ 1.8m 4.6m  + beam orbit diameter 0.66m 2.1m round (cyclotron period=7.4 nsec) 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 Upper half

2010/9/28 14 Beam acceptance study is ongoing Start ++  y <0 Solenoid axis  y>0  y >0  y<0 y Beam acceptance

Coil Vertical kicker (ver.0) 2010/9/28 15 Helmholtz type Br(t)=B peak  sin(  t)  Apply radial magnetic field to reduce beam vertical momentum  Prototype kicker is being designed for test. ±10cm STOP!

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  Saturday 10:00 Prof. B. Lee Roberts Active R&D efforts are ongoing! My next step: Verification test for injection + kicker system /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 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 Thank you! 2010/9/28

Backups 2010/9/28 18

Requirements for Kicker 19 Br(t)=B peak  sin(  t)  =  /T kick Field strength ： B peak = 1Gauss ~ 10 Gauss Time distribution ： T kick =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 e + detector (Silicon tracker) 2010/9/28