T EDM P Spin EDM Spin Search for

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+ + T + _ _ EDM _ P Spin EDM Spin Search for

+ + T + _ _ EDM _ P Spin EDM Spin Search for a Permanent Electric Dipole Moment (EDM) of Radium-225 Zheng-Tian Lu Physics Division, Argonne National Laboratory Department of Physics, University of Chicago

T = CP More CP-Violation Mechanisms? Strong CP problem CP-violating phase in Quantum Chromodynamics

T = CP More CP-Violation Mechanisms? Strong CP problem CP-violating phase in Quantum Chromodynamics Supersymmetry More particles More CP-violating phases Matter-antimatter asymmetry Require additional CP-violation mechanism(s)

Intensity Frontier Workshop, Dec 2011, www. intensityfrontier. org Convenors for nuclear physics: Haxton, Lu,

Intensity Frontier Workshop, Dec 2011, www. intensityfrontier. org Convenors for nuclear physics: Haxton, Lu, Ramsey-Musolf Priorities according to Nima Arkani-Hamed, Institute for Advanced Study “The existence of an EDM can provide the “missing link” for explaining why the universe contains more matter than antimatter. ” “A nonzero EDM would constitute a truly revolutionary discovery. ” -- Nuclear Science Advisory Committee (NSAC) Long Range Plan (2007) “The non-observation of EDMs to-date, thus provides tight restrictions to building theories beyond the Standard Model. ” -- P 5 report : The Particle Physics Roadmap (2006)

EDM Searches in Three Sectors Quark EDM Nucleons (n, p) Diamagnetic atoms (Hg, Ra,

EDM Searches in Three Sectors Quark EDM Nucleons (n, p) Diamagnetic atoms (Hg, Ra, Rn) Quark Chromo-EDM 4 Fermion, 3 Gluon Electron in paramagnetic molecules (Yb. F, Th. O) Electron EDM, Electron-Quark Physics beyond the Standard Model: SUSY, etc. Sector Exp Limit (e-cm) Method Standard Model Electron 9 x 10 -29 Th. O in a beam 10 -38 Neutron 3 x 10 -26 UCN in a bottle 10 -31 199 Hg 3 x 10 -29 Hg atoms in a cell 10 -33 M. Ramsey-Musolf (2009)

Ds Rg Cn Uut Fl 11 S S 00 Uup Lv Uus Uuo

Ds Rg Cn Uut Fl 11 S S 00 Uup Lv Uus Uuo

EDM of 225 Ra enhanced and more reliably calculated • Closely spaced parity doublet

EDM of 225 Ra enhanced and more reliably calculated • Closely spaced parity doublet – Haxton & Henley, PRL (1983) • Large Schiff moment due to octupole deformation – Auerbach, Flambaum & Spevak, PRL (1996) • Relativistic atomic structure (225 Ra / 199 Hg ~ 3) – Dzuba, Flambaum, Ginges, Kozlov, PRA (2002) Parity doublet |a - = |b (|a - |b )/ 2 55 ke. V + = (|a + |b )/ 2 Enhancement Factor: EDM (225 Ra) / EDM (199 Hg) Isoscalar Isovector Skyrme SIII 300 4000 Skyrme Sk. M* 300 2000 Skyrme SLy 4 700 8000 Schiff moment of 225 Ra, Dobaczewski, Engel, PRL (2005) Schiff moment of 199 Hg, Dobaczewski, Engel et al. , PRC (2010) “[Nuclear structure] calculations in Ra are almost certainly more reliable than those in Hg. ” – Engel, Ramsey-Musolf, van Kolck, Prog. Part. Nucl. Phys. (2013) Constraining parameters in a global EDM analysis. – Chupp, Ramsey-Musolf, ar. Xiv 1407. 1064 (2014)

EDM measurement on 225 Ra in a trap 225 Ra: I=½ t 1/2 =

EDM measurement on 225 Ra in a trap 225 Ra: I=½ t 1/2 = 15 d Collaboration of Argonne, Kentucky, Michigan State • Efficient use of the rare 225 Ra atoms • High electric field (> 100 k. V/cm) Oven: 225 Ra • Long coherence time (~ 100 s) • Negligible “v x E” systematic effect Transverse cooling Zeeman Slower Magneto-optical Trap (MOT) Statistical uncertainty 100 d 100 k. V/cm 100 s 106 Long-term goal: dd = 3 x 10% 10 -28 e cm EDM measurement Optical dipole trap (ODT)

Apparatus Argonne National Lab 8

Apparatus Argonne National Lab 8

EDM (d) Measurement B ~ 10 m. Gauss B-field spatial variation < 0. 1%/cm

EDM (d) Measurement B ~ 10 m. Gauss B-field spatial variation < 0. 1%/cm B-field temporal variation < 0. 01% (50 sec) Emax = 75 k. V/cm E-field spatial variation < 1%/mm

Oct. 2014 Radium EDM Data Dec. 2014 d. Ra-225 = (-0. 5 ± 2.

Oct. 2014 Radium EDM Data Dec. 2014 d. Ra-225 = (-0. 5 ± 2. 5 stat ± 0. 2 syst) × 10 -22 e-cm |d. Ra-225| < 5. 0 × 10 -22 e-cm (95% confidence)

 • First EDM measurement on octupole deformed nuclei; • First EDM measurement using

• First EDM measurement on octupole deformed nuclei; • First EDM measurement using cold atoms.

Outlook • 2015 - 2016 • Longer trap lifetime; • Implement STIRAP – more

Outlook • 2015 - 2016 • Longer trap lifetime; • Implement STIRAP – more efficient way to detect spin; • 2016 - 2018, blue upgrade – more efficient trap; • Five-year goal (before FRIB): 10 -26 e cm; • 2020 and beyond (at FRIB): 3 x 10 -28 e cm; • Far future: search for EDM in diatomic molecules • Effective E field is enhanced by a factor of 103; • Reach the Standard Model value of 10 -30 e cm.

Absorption Detection of Spin State F = 3/2 1 P 1 Photons scattering events

Absorption Detection of Spin State F = 3/2 1 P 1 Photons scattering events 2 -3 photons per atom F = 1/2 Signal-to-noise Ratio For 100 atoms, SNR ~ 0. 2 483 nm 1 S 0 F = 1/2 m. F = -1/2 +1/2

STIRAP (stimulated Raman adiabatic passage) F = 3/2 1 P 1 F = 1/2

STIRAP (stimulated Raman adiabatic passage) F = 3/2 1 P 1 F = 1/2 1429 nm 483 nm 3 D 1 S 0 1 F = 1/2 m. F = -1/2 +1/2 Stimulated, Adiabatic process No fluorescence

Absorption Detection on a Cycling Transition m. F = +3/2 F = 3/2 1

Absorption Detection on a Cycling Transition m. F = +3/2 F = 3/2 1 P 1 Photons scattering events 2 -3 photons per atom 100 -1000 photons per atom F = 1/2 Signal-to-noise Ratio For 100 atoms, SNR ~ 0. 2 For 100 atoms, SNR ~ 10 483 nm 3 D 1 S 0 F = 1/2 m. F = -1/2 +1/2 1

Improve trapping efficiency with a blue upgrade 7 p 1 P 6 ns 7

Improve trapping efficiency with a blue upgrade 7 p 1 P 6 ns 7 p 1 P 11 6 ns P Puum m p p #1 #1 6 d 1 D 2 430 ms 420 ns 7 p 3 P 11 Slo w& Tr. Ta rpa, p 7 , 1741 n 4 m nm 6 d 3 D 2 7 s 2 1 S 00 6 d 3 D 11

Improve trapping efficiency with a blue upgrade Pu 3 # mp P Puum m

Improve trapping efficiency with a blue upgrade Pu 3 # mp P Puum m p p #1 #1 #2 420 ns 7 p 3 P 11 6 d 3 D 2 Slo w& Tr. Ta rpa, p 7 , 1741 n 4 m nm Slow, 483 nm p m Pu 6 d 1 D 2 430 ms 6 d 3 D 11 KVI barium trap S. De et al. PRA (2009) Scheme • 1 st slowing laser: 483 nm (strong) • 2 nd slowing laser: 714 nm • 3 repumpers: 1428 nm, 1488 nm, 2. 75 mm • 171 Yb as co-magnetometer * 225 Ra and 171 Yb trapped, < 50 mm apart Benefits • 100 times more atoms in the trap • Improved control on systematic uncertainties 310 m/s Atom Flux 7 p 1 P 6 ns 7 p 1 P 11 6 ns 60 m/s 7 s 2 1 S 00 Atom Velocity

233 U 225 Ra Yields a 225 Ac a Fr, Rn, … ~4 hr

233 U 225 Ra Yields a 225 Ac a Fr, Rn, … ~4 hr 10 d 229 Th b a 7. 3 kyr 225 Ra 15 d Presently available • National Isotope Development Center, ORNL • Decay daughters of 229 Th 225 Ra: Projected • FRIB (B. Sherrill, MSU) • Beam dump recovery with a 238 U beam • Dedicated running with a 232 Th beam 6 x 109 /s 5 x 1010 /s • • 159 kyr ISOL@FRIB (I. C. Gomes and J. Nolen, Argonne) • Deuterons on thorium target, 1 m. A x 400 Me. V = 400 k. W 1013 /s MSU K 1200 (R. Ronningen and J. Nolen, Argonne) • Deuterons on thorium target, 10 u. A x 400 Me. V = 4 k. W 1011 /s 108 /s 18

Michael Bishof Peter Mueller Richard Parker Tom O’Connor Z. -T. Lu Kevin Bailey Mukut

Michael Bishof Peter Mueller Richard Parker Tom O’Connor Z. -T. Lu Kevin Bailey Mukut Kalita Roy Holt Cold Atom Trappers Argonne: Kevin Bailey, Michael Bishof, John Greene, Roy Holt, Nathan Lemke, Zheng-Tian Lu, Peter Mueller, Tom O’Connor, Richard Parker Kentucky: Mukut Kalita, Wolfgang Korsch Michigan State: Jaideep Singh Northwestern: Matt Dietrich

Optical Dipole Trap • Fiber laser: l = 1550 nm, Power = 40 Watts

Optical Dipole Trap • Fiber laser: l = 1550 nm, Power = 40 Watts • Focused to 100 mm trap depth 400 m. K EDM in an optical dipole trap – Fortson & Romalis (1999) • • • v x E , Berry’s phase effects suppressed Cold scattering suppressed between cold Fermionic atoms Rayleigh scat. rate ~ 10 -1 s-1 ; Raman scat. rate ~ 10 -12 s-1 Vector light shift ~ m. Hz Parity mixing induced shift negligible Conclusion: possible to reach 10 -30 e cm for 199 Hg

Trap Lifetimes MOT & ODT Sideview Magneto-Optical Trap (MOT) in the first trap chamber

Trap Lifetimes MOT & ODT Sideview Magneto-Optical Trap (MOT) in the first trap chamber Head-on view ODT 0. 04 mm Optical Dipole Trap (ODT) in the EDM chamber

Systematics • Systematic effects much smaller than Statistical error for now • No corrections

Systematics • Systematic effects much smaller than Statistical error for now • No corrections needed Systematic Effect Imperfect E-field reversal Blue laser frequency correlations External B-field correlations Current supply correlations E-field pulsing 1 D MOT Coil Magnetization Leakage current Optical lattice power correlations E x v effects Stark interference Berry’s phase Δd. Ra-225 (e-cm) 1 × 10 -23 < 10 -25

E 2 Systematic 3 m. Ci Run (October) d. E-squared syst ≤ 0. 2×

E 2 Systematic 3 m. Ci Run (October) d. E-squared syst ≤ 0. 2× 10 -22 e-cm 6 m. Ci Run (December) d. E-squared syst ≤ 0. 05× 10 -22 e-cm

What the stat. sensitivity of our experiment could be! Actual Near Term Goal N:

What the stat. sensitivity of our experiment could be! Actual Near Term Goal N: # atoms detected 150 300 E: Effective E-field (k. V/cm) 45 75 �� : Precession Time (s) 2 20 Td: Dead time (s) 48 48 T: Total time (s) 2 × 86, 400 5 × 86, 400 γatom: Photons per atom 2. 5 1, 000 γlaser: Photons per laser pulse 106 4× 108 EDM sens. (e-cm) 3× 10 -22 4× 10 -25

Why a more sensitive radium EDM measurement is important to science T. Chupp and

Why a more sensitive radium EDM measurement is important to science T. Chupp and M. Ramsey-Musolf, ar. Xiv. 1407. 1064

Preparation of Cold Radium Atoms for EDM • 2006 – Atomic transitions identified and

Preparation of Cold Radium Atoms for EDM • 2006 – Atomic transitions identified and studied; N. D. Scielzo et al. , PRA Rapid 73, 010501 (2006) • 2007 – Magneto-optical trap (MOT) of radium realized; J. R. Guest et al. , PRL 98, 093001 (2007) • 2010 – Optical dipole trap (ODT) of radium realized; • 2011 – Atoms transferred to the measurement trap; R. H. Parker et al. , PRC 86, 065503 (2012) • 2012 – Spin precession of Ra-225 in ODT observed; • 2014 – First measurement of EDM of Ra-225. R. H. Parker et al. , submitted

EDM (d) Measurement

EDM (d) Measurement