2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014)

June 1-6, 2014, Tokyo, Japan

129Xe EDM search experimentusing active nuclear spin maser

Tokyo Institute of Technology
Tomoya SATOEDM, the new physics indicator
matterAnti-matter

Electric dipole moment

s+++

d−−−

<<𝒔𝒅=𝑑𝑠
T-violation
Standard Model

Supersymmetry

Discovery of the finite value of the EDM
Discovery of the new physics beyond the SM!!
2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan1

The origin of atomic EDM
Schiff moment+-1
𝑺ch =10+ -𝐴𝑒𝑖 𝑟𝑖2 −𝑖=1

5 2𝑟 ch 𝒓𝑖
3- From a shell model point of view
N. Yoshinaga et al.
Phys. Rev. C 87, (2013) 044332

Schiff moment
Tl, Fr, Cs…

129Xe, 199Hg, Rn, Ra…

-1/2 states

M. Pospelov and A. Ritz,
Annals of Phys. 318, (2005) 119-169

Energy gap~ ħ𝜔 ~ 9MeV

The atomic EDM of the 129Xe•EDM is generated through the Schiff moment(P,T-odd NN interaction, reflect nuclear structure)•Stable nuclei, huge amount of atoms ( ～1023)+1/2 g. s.

ν・・・1+1−𝑆
21 ch,z 2𝑘𝑆(𝑘) =(+)

𝑘=1

2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan

𝐸1

1− 𝑃𝑇 1+𝑉 2
2𝑘 𝜋1(−)− 𝐸𝑘+ c. c.
2Current status of the EDM searches
Prediction value of the EDM

10-27

10-24

10-31

10-28

10-33 10-30
129Xe
neutronOur target|d(129Xe)| = 10-28e·cm
E = 10 kV/cm

StandardModel(dn = 10-(31-33) )|d(199Hg)| < 3.1×10-29 ecm
Griffith et al., PRL 102 (2009) 101601|d(129Xe)| < 4.1×10-27 ecm[Pendlebury and Hinds, NIM A 440 (00) 471]

Rosenberry and Chupp, PRL 86 (2001) 22
2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan3

How to measure the EDM
 Energy splitting changes due to the EDM
𝑩𝑬𝑩𝑩

𝑬

𝜈+

𝜈−ℎ𝜈+ℎ𝜈−𝜈0𝑚 = −1/2ℎ𝜈0

𝑩=0
𝑬=0𝑚 = +1/2 𝑩 ≠ 0

𝑬=0

𝑩≠0−𝑬 // 𝑩

𝑩≠0𝑬 // 𝑩

2𝜇𝐵 + 2𝑑𝐸
ℎ2𝜇𝐵 − 2𝑑𝐸
𝜈− =ℎ𝜈+ =ℎ∆𝜈4𝐸(∆𝜈 = 𝜈+ − 𝜈− )𝑑=Transverse spin Consecutive measurement of spin precession (Maser) final Tm11 Tm-3 / 2 : Fourier width :  TmTm  data points: Tm  1/ 2

2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan

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Active nuclear spin maser“Optically manipulated” spin maser
with a feedback field generated by optical spin detection
129Xe

Static magnetic field :Feedback system
𝑩0 ∼ mG
Probe
Feedback
light
Feedback
coil
circuit

Rb

IS

129Xe

Feedback
FieldRb

𝐻 = 𝛼𝑰 ⋅ 𝑺= 𝛼2 𝐼+ 𝑆− +𝐼− 𝑆+ +𝛼𝐼z 𝑆z

Lock-indetection

Xe polarization
Photodiode129XeRe-polarization

Pumping light

Precession signal

Rb
Probe light

A. Yoshimi et al., Phys. Lett. A 304 (2002) 13.
A. Yoshimi et al., Phys. Lett. A 376 (2012) 1924.

2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan5

Frequency precision of 129Xe maser
Frequency precisionin one-shot measurementΔ𝜈 ∼ 10 nHz～10 nHz

Frequency stability
between repeatedmeasurements～1 mHzΔ𝜈 ∼ 1 mHz

Long term driftsof the external magnetic field
2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan6

3He co-magnetometry

 129Xe frequency:
B0 + EDM

 3He frequency:

B0 in situ magnetometry Negligible EDM in 3He
 Correlation in phase：𝛷Xe 𝑡𝛾Xe=
𝛷 (𝑡)𝛾He He2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan

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Contact interaction with pol. Rb atoms
𝝂𝟏𝟐𝟗

𝐗𝐞 =𝜸 𝟏𝟐𝟗𝐗𝐞𝟐𝝅

𝑩𝟎 + 𝜿𝐑𝐛−𝐗𝐞 𝐑𝐛 𝑷𝐑𝐛 ±𝟒𝒅𝑬𝒉EDM factor

Static & Env. mag. field Freq. shift due to pol. Rb
𝝂𝟑𝐇𝐞 =𝜸 𝟑𝐇𝐞𝟐𝝅

𝑩𝟎 + 𝜿𝐑𝐛−𝐇𝐞 𝐑𝐛 𝑷𝐑𝐛※3He EDM is assumed
to be negligible

Frequency shift of 129Xe/3He due tocontact interaction with polarized RbΔ𝜈 ∝ 𝜅 Rb 𝑃Rb
Rb numberdensity

RbPolarization

𝜅0 Xe−Rb = 493(31) [1]𝜅0 He−Rb = 4.52 + 0.00934𝑇 [2][1] Z. L. Ma et al., Phys. Rev. Lett. 106, 193005 (2011)[2] M. V. Romalis et al., Phys. Rev. A 58, 3004 (1998)

2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan8

Reduction of the pol. Rb atoms:129Xe:3He:Rb

Pumping region
Pumping laser

ΔνXe/He (Maser frequency shift)∝ κXe/He(Coefficient) × [Rb] × PRb

Probe region

Linearly polarizedlaser light-

Double cell geometry-

Linearly polarized laser light

Probe laserAdvantages

 Reduce PRb at probe section
 Different temperature at pumping & probe sections
Difficulties

 Reduction of P (129Xe) as diffusion
 Reduction of maser signal due to reduced PRb
2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan9

Experimental setup
Photo diode3 layer magnetic shield𝜆/4 platePBS

Static magnetic field coilB0
Photo Elastic
Modulator

𝜆/2 plate

2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan

Pumping laser
wave length：794.76 nm（Rb D1 line）
line width：～10 MHz
output：1.8 W
Probe laser
wave length：794.76 nm（depend onmeasurement condition)line width：～10 MHz
output：10 mW
10Experimental setup
Magnetic shield

Env. fieldcancellation coil

Lin. Pol. light
Probe light

Pumping light11

Dual spin maser with double cell geometry
129Xe

Time [s]Time [s]3He3HeTime [s]Time [s]He signal output [V]Xe signal output [V]129XeFirst trial of 129Xe/3He dual spin maser with double cell geometry
2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan12

129Xe/3He frequency analysis (1)3He frequency [Hz]129Xe frequency [Hz]Maser frequencies (stable region, 100s averaged)

time [s]2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan

time [s]133He/129Xe frequency ratio

3He/129Xe frequency ratio

129Xe/3He frequency analysis (2)Cell temperature [℃]

Temperature [℃]time [s]2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japanverification is continued.
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Towards measurement of Xe-EDM
Birth of the active feedback spin maser
Maser stability improvement(B-field, temperature, gas pressure, etc…)
EDM measurement trial with spherical cell
3He/129Xe maser (spherical cell)

Xe-EDM
Measurement

Double cell geometry
3He/129Xe maser (double cell)

Remaining (on going) steps- Verification of 3He co-magnetometry- Development of EDM cell with transparent electrodes2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan15

Summary and future plan

Search for 129Xe EDM aiming at 10-28 ecm region
Active nuclear spin maser
Optical detection of spin + Artificial feedback

Development
 3He co-magnetometry (reduce B-field fluctuation)
Double-cell geometry (minimize interaction with pol. Rb)
Dual spin masers of 129Xe/3He using double cellFuture outlook
Evaluation of systematic uncertainty
EDM cell (with Electrode) development
EDM measurement
2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan16

Collaborators
Tokyo Institute of Technology
T. Sato, Y. Ohtomo, Y. Sakamoto, S. Kojima, T. Suzuki, H. Shirai,
M. Chikamori, E. Hikota, H. Miyatake, T. Nanao, K. Suzuki,
M. Tsuchiya, K. Asahi

RIKEN Nishina Center

Tohoku University

Y. Ichikawa, H. Ueno

Tokyo Metropolitan University

T. Inoue

Okayama University

T. Furukawa

University of Winnipeg
C. P. Bidinosti

Hosei University
Y. Matsuo

A. Yoshimi

KEKT. Ino

RCNP, Osaka University
T. Fukuyama

2nd Conference on Advances in Radioactive Isotope Science (ARIS 2014), June 1-6, 2014, Tokyo, Japan

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