Yannis K. Semertzidis Brookhaven National Laboratory Seminar IUCF, 21 May 2004 EDMs: Why are they important? Our Universe: The Symmetry that isn’t EDM Experimental Techniques EDMs in Storage Rings Prospects of the Field EDMs in Storage Rings: Powerful Probes of Physics Beyond the SM and of CP-Violation

Questions Physicists Ask:

A Permanent EDM Violates both T & P Symmetries:

Spin is the only vector… Phenom.: only the component along the spin survives

A Permanent EDM Violates both T & P Symmetries: T P

P T

Reality Check: Induced EDMs… T OK P 1 st order Stark effect. Forbidden! 2 nd order Stark effect. Allowed!

Reality Check: MDMs are Allowed… T P

T-Violation CP-Violation CPT Andrei Sakharov 1967: CP-Violation is one of three conditions to enable a universe containing initially equal amounts of matter and antimatter to evolve into a matter-dominated universe, which we see today….

Before 1929: Universe is Static-Eternal Cosmological Constant is Invented to Stabilize it! Dirac Equation 1928: 1.g=2 for Point-like, Spin ½ Particles 2.Negative Energy States Flashback

Hubble 1929: Universe is Expanding …If the Universe Expands…  a Beginning and a BIG BANG! Km/MPa/s or s -1 Discovery of Positron by Anderson: 1933

At Accelerators: 1955: Antiproton Discovery at Berkeley 1956: Antineutron Discovery 1957: Parity Violation, Lee-Yang 1964: CP-Violation at Brookhaven Universe: Matter Dominated; Initial Condition Maintained by B, L Number Conservation.

Andrei Sakharov 1967: Three conditions to enable a universe containing initially equal amounts of matter and antimatter to evolve into a matter-dominated universe, which we see today: Proton Decay (Baryon Number Violation) CP-Violation Universe Undergoes A Phase of Extremely Rapid Expansion

Extension of the SM Needed? SM: CP-Violation not Enough by Several Orders of Magnitude for Baryogenesis

SM Versus SUSY: One CP-Violating Phase (CKM). SM: 42 CP-Violating Phases! SUSY:

 á  la Fortson d

Usual Experimental Method Small Signal Compare the Zeeman Frequencies When E-field is Flipped: + - 

Schiff Theorem: A Charged Particle at Equilibrium Feels no Force… …An Electron in a Neutral Atom Feels no Force Either: …Otherwise it Would be Accelerated…

Neutron EDM Vs Year

Neutron EDM at LANSCE Aiming for a Factor of 50

3

Q=CV

S. Lamoreaux at “Lepton Moments”, June 2003 E=5MV/m, T=10 8 s R&D

Cost of the n-EDM Experiment at LANSCE $10M for the experimental apparatus $9M for the Beamline R&D? Total $19M plus R&D

Schiff Theorem: A Charged Particle at Equilibrium Feels no Force… …An Electron in a Neutral Atom Feels no Force Either. However: …the net E-field is not zero!

Experimental Limit on d e (e. cm) Electron EDM Cs Xe* Hg Cs Tl ?? Tl

Current Atomic EDM Limits Paramagnetic Atoms, 205 Tl: electron |d e | < 1.6  e·cm (90%CL) PRL 88, (2002) Diamagnetic Atoms, 199 Hg Nucleus: |d( 199 Hg)| < 2.1  e·cm (95%CL) PRL 86, 2505 (2001)

Electric Dipole Moments in Storage Rings e.g. 1T corresponds to 300 MV/m!

Spin Precession in g-2 Ring (Top View)  Momentum vector Spin vector

Spin Precession in g-2 Ring (Top View)  Momentum vector Spin vector

The Muon Storage Ring: B ≈ 1.45T, P μ ≈3.09 GeV/c

4 Billion e + with E>2GeV

B Ron McNabb’s Thesis 2003: x y z s β Indirect Muon EDM limit from the g-2 Experiment

Canceling g-2 with a Radial E-field x y z s β B 

Radial E-field to Cancel/Control the g-2 Precession Radial E-Field: The method works well for particles with small anomalous magnetic moment a, e.g. Muons (a = ), Deuterons (a = ), etc.

Spin Precession in g-2 Ring (Top View)  Momentum vector Spin vector

Spin Precession in EDM Ring (Top View)  Momentum vector Spin vector

The muon spin precesses vertically (Side View)

Two Major Ideas: Radial E-field to Cancel the g-2 Precession Injecting CW and CCW Sensitivity: e·cm statistical (1 yr, 0.75MW) Sensitivity: e·cm systematic error Muon EDM LOI: ( to J-PARC.

Muon EDM Letter of Intent to J-PARC/Japan, 2003 † Spokesperson # Resident Spokesperson † † #

Expected Muon EDM Value from a 

Predictions in Specific Models The predicted value for the electron is 10 times less than the current experimental limit. 50  effect at e  cm Exp. Sensitivity!

Predictions in Specific Models Experimental Goal T. Feng, et al., hep-ph/ “Lepton Dipole Moments and Rare Decays in the CP-Violating MSSM with Non-Universal Soft-Supersymmetry Breaking”

g-2 Values Electron0.0016done Muon0.0016doing Proton Deuteron-0.15OK!

Deuteron Coherence Time E, B field stability Multipoles of E, B fields Vertical (Pitch) and Horizontal Oscillations Finite Momentum Acceptance ΔP/P At this time we believe we can do  p ~10s

Deuteron EDM Signal: Radial E-Field: e.g. for E R = 3.5MV/m, d = e·cm; ω d = 0.3µrad/s

Enhancement of EDM Signal by Canceling the g-2 Precession Edm Signal Rate: 0.3  rad/s With Cancellation:  a  0.1 rad/s; Max vertical spin amplitude within 10s:  1  rad Without Cancellation:  a  10 6 rad/s; Max vertical spin amplitude within 10s:  0.1prad

Nuclear Scattering as Deuteron EDM polarimeter IDEA: - make thick target defining aperture - scatter into it with thin target D L U R R D Δ “extraction” target - ribbon “defining aperture” primary target detector system Target could be Ar gas (higher Z). Target “extracts” by Coulomb scattering deuterons onto thick main target. There’s not enough good events here to warrant detectors. Hole is large compared to beam. Every- thing that goes through hole stays in the ring. Detector is far enough away that doughnut illumination is not an acceptance issue: Δ < R. Ed Stephenson’s

Deuteron Statistical Error (200MeV):  p : 10s. Polarization Lifetime (Coherence Time) A : 0.5 The left/right asymmetry observed by the polarimeter P : The beam polarization N c : 4  d/cycle. The total number of stored particles per cycle T Tot : 10 7 s. Total running time per year f : 0.01 Useful event rate fraction E R : 3.5MV/m. Radial electric field per year

Sources of Deuteron Systematic Errors: Out of Plane Electric Field (E v ) Geometrical Phases (2 nd Order Effects) Tensor Polarization (E.S.: Different Dependence on  a …) Polarimeter Detector Related Effects

Effect of Vertical Component of E Deuterons β=0.2, γ=1.02, ω=13  10 5  θ E rad/s

CW vs CCW B B EE E-Field does NOT flip sign!

Effect of Vertical Component of E Clock Wise and Counter-Clock Wise Injection: Background: Same Sign Signal: Opposite Sign Protons β=0.15, γ=1.01, ω  100  10 5  θ E rad/s Deuterons β=0.2, γ=1.02, ω  10  10 5  θ E rad/s Muons β=0.98, γ=5, ω  2  10 5  θ E rad/s Other Diagnostics Include Injecting Forward vs Backward Polarized Beams as well as Radially Pol.

E v Issues: Temporal Changes (CW and CCW every 10s) Changes Correlated with B-Field Reversals (Fabry-Perot Resonator) E-Field Multipoles Couple to Beam Moments (Pickup Electrodes; Beam Moment Manipulation)

Tilt-meter Measurements at the g-2 Ring with 1nrad Resolution

Systematic Error Symmetries (+) Same as EDM; (-) is opposite Spin Related Polarimeter Related

Deuteron EDM Ring Lattice

Deuteron EDM Signal is Strong: Radial E-field Controls g-2 Precession Rate Intense Polarized Deuteron Beams Long Spin Coherence Time  10s Polarimeters: Large Left/Right Asymmetry

Deuteron EDM Systematics: E V : CW vs CCW Injection Geometrical Phases: Local Cancellation of g-2 and CW vs CCW Injection Preliminary Flattening of Ring to rad: Beam Dynamics Resonance and Beam Position Monitors. The Spin Itself is Sensitive… Detector Related Effects: CW vs CCW Injection, Spin Flip at Injection Leakage Current is a Second Order Effect!

Deuteron EDM to e  cm Sensitivity Level is 100 times better than 199 Hg T-odd Nuclear Forces: d d =2  ξ e·cm with the best limit for ξ<0.5  coming from the 199 Hg EDM limit (Fortson, et al., PRL 2001), i.e. d d < e·cm. (Sushkov, Flambaum, Khriplovich Sov. Phys. JETP, 60, p. 873 (1984) and Khriplovich and Korkin, Nucl. Phys. A665, p. 365 (2000)).

d d = d p + d n (I. Khriplovich) It Improves the Current Proton EDM Limit by a Factor of ~10,000 and a Factor on Neutron.

Deuteron (D) EDM at 3  e  cm Relative strength of various EDM limits as a function of left handed down squark mass (O. Lebedev, K. Olive, M. Pospelov and A. Ritz, hep- ph/ )

Possible Locations for a Deuteron EDM Experiment: Brookhaven National Laboratory Indiana University Cyclotron Facility KVI/The Netherlands Proposal This Year… $20-30M 

We are Studying Target and Polarimetry (Deuteron case) E-field Directional/Amplitude Stability Beam and Spin Dynamics

EDMs Questions Physicists Ask:

Electric Dipole Moment Searches: Exciting Physics, Forefront of SUSY/Beyond SM Search. Revolutionary New Way of Probing EDMs, Muon and Deuteron Cases-Very Exciting. EDM Experiments could Solve the Long Standing Mystery of Matter Asymmetry in our Universe Summary

Extension of the SM Needed? SM: CP-Violation not Enough by Several Orders of Magnitude for Baryogenesis Leptogenesis: CP-Violation in Neutrino Mixing? Heavy, Weakly Interacting, Right-Handed Neutrinos Produced in Early Universe Their Decays Produces Lepton Number Asymmetry. Further Interactions Conserving B-L Convert it to Baryon Number Asymmetry

Parameter Values of Muon EDM Experiment Radial E-Field: E=2MV/m Dipole B-field: B~0.25T Muon Momentum: Need NP 2 =10 16 for e. cm. Muon EDM LOI: ( to J-PARC, <one year of running.

d(muon) < 7   Left-Right d e.cm Multi Higgs SUSY  Electro- magnetic neutron: electron: Current status of EDMs d(electron) < 1.6  d(neutron) < 6  d(proton) < 6    la Sauer d( 199 Hg) < 2.1 

E-field Stability: Major Breakthrough Idea by Neil Shafer-Ray E-field Stability of Order to 10 -9

Parameter Values of Muon EDM Experiment Radial E-Field: E=2MV/m Dipole B-field: B ~ 0.25T, R ~ 10m Muon Momentum: Need NP 2 =10 16 for e. cm. Muon EDM LOI: ( to J-PARC, <one year of running. F. Farley et al., hep-ex/

Parameter Values of a Deuteron EDM Experiment Radial E-Field: E R =3.5MV/m Dipole B-field: B~ T; Ring Radius: R~15-30m Deuteron Momentum: YkS et al., hep/ex

Deuteron EDM to e  cm Sensitivity Level is 100 times better than 199 Hg T-odd Nuclear Forces: d d =2  ξ e·cm with the best limit for ξ<0.5  coming from the 199 Hg EDM limit (Fortson, et al., PRL 2001), i.e. d d < e·cm. (Sushkov, Flambaum, Khriplovich Sov. Phys. JETP, 60, p. 873 (1984) and Khriplovich and Korkin, Nucl. Phys. A665, p. 365 (2000)).

d d = d p + d n (I. Khriplovich) It Improves the Current Proton EDM Limit by a Factor of ~10,000 and a Factor on Neutron.

Possible Improvements: Higher E R Fields: 14MV/m with gas to slow down free electrons. Longer Storage Time than 10s while Maintaining Polarization (Coherence Time).

Deuteron Statistical Error:  p : Polarization Lifetime (Coherence Time) A : The left/right asymmetry observed by the polarimeter P : The beam polarization N c : The total number of stored particles per cycle T Tot : Total running time f : Useful event rate fraction E R : Radial electric field

Signal and Background: