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Fundamental Interactions Trento/Italy, 21-25 June 2004. Muon EDM in Storage Rings: Probing the Second Generation. Yannis K. Semertzidis Brookhaven National Laboratory. EDM Experimental Techniques EDMs in Storage Rings. á la Fortson. d. ~.
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Fundamental Interactions Trento/Italy, 21-25 June 2004 MuonEDM in Storage Rings: Probing the Second Generation. Yannis K. Semertzidis Brookhaven National Laboratory • EDM Experimental Techniques • EDMs in Storage Rings
ála Fortson d ~ Muon EDM in SM <10-38e cm, I. Khriplovich.
E Small Signal + Compare the Zeeman Frequencies When E-field is Flipped: - Usual Experimental Method
Electron EDM 10-20 Cs 10-22 Cs 10-24 Xe* Hg Experimental Limit on de (e .cm) Cs 10-26 Tl Tl Tl ?? 10-28 10-30 1960 1970 1980 1990 2000 2010
Current Atomic EDM Limits • Paramagnetic Atoms, 205Tl: electron |de| < 1.610-27e·cm (90%CL) PRL 88, 071805 (2002) • Diamagnetic Atoms, 199Hg Nucleus: |d(199Hg)| < 2.110-28e·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 m Spin vector
Spin Precession in g-2 Ring(Top View) Momentum vector m Spin vector
Indirect Muon EDM limit from the g-2 Experiment z y s β x B Ron McNabb’s Thesis 2003:
Canceling g-2 with a Radial E-field z B E y s β x
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 = 0.0011), Deuterons (a = -0.143), etc.
Effect of E-Field to g-2 Precession In a B-Field In an E-Field
Momentum vector Spin vector Spin Precession in g-2 Ring(Top View) m
Momentum vector Spin vector Spin Precession in EDM Ring(Top View) m
Sources of Muon Systematic Errors: • Out of Plane Electric Field (Ev) • Geometrical Phases (2nd Order Effects) • Detector Related Effects • Beam Motion During Storage
E E CW vs CCW B B 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, ω100105 θE rad/s • Deuterons β=0.2, γ=1.02, ω 10105 θE rad/s • Muons β=0.98, γ=5, ω 2105 θE rad/s • Other Diagnostics Include Injecting Forward vs Backward Polarized Beams as well as Radially Pol.
Ev 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
Spin Related Systematic Error Symmetries:(+) Same as EDM; (-) is opposite
Two Major Ideas: • Radial E-field to Cancel the g-2 Precession • Injecting CW and CCW • Sensitivity: 10-24 e·cm statistical (1 yr, 0.75MW) • Sensitivity: 10-27 e·cm systematic error • Muon EDM LOI: (http://www.bnl.gov/edm) to J-PARC.
Muon EDM Letter of Intent to J-PARC/Japan, 2003 † † # • †Spokesperson • # Resident Spokesperson
Parameter Values of Muon EDM Experiment • Radial E-Field: • E=2MV/m • Dipole B-field:B~0.25T, R~10m • Muon Momentum:
Statistical Error (Muon Case): : 11s. Muon Lifetime A : 0.3 Vertical Asymmetry NTot P2: 51016 The beam intensity at J-PARC per year. ER : 2MV/m Radial electric field value per year
Predictions in Specific Models 50 effect at 10-24 ecm Exp. Sensitivity! The predicted value for the electron is 10 times less than the current experimental limit.
Linear Mass Scaling of Lepton EDM is Avoided in Specific Models • A. Pilaftsis, Nucl. Phys. B644 (2002) 263 • T. Feng et al., hep-ph/0305290
g-2 Values • Electron 0.0016 done • Muon 0.0016 doing • Proton 1.8 ------ • Deuteron -0.15 OK!
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 ER = 3.5MV/m, d = 10-27e·cm; ωd = 0.3µrad/s
Enhancement of EDM Signalby Canceling the g-2 Precession • Edm Signal Rate: 0.3rad/s • With Cancellation:a 0.1 rad/s; Max vertical spin amplitude within 10s: 1rad • Without Cancellation:a 106 rad/s; Max vertical spin amplitude within 10s: 0.1prad
Deuteron Statistical Error (200MeV): p : 10s. Polarization Lifetime (Coherence Time) A : 0.5 The left/right asymmetry observed by the polarimeter P : 0.55. The beam polarization Nc: 41011d/cycle. The total number of stored particles per cycle TTot: 107s. Total running time per year f : 0.01 Useful event rate fraction ER : 3.5MV/m. Radial electric field per year
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: • EV: CW vs CCW Injection • Geometrical Phases: Local Cancellation of g-2 and CW vs CCW Injection • Preliminary Flattening of Ring to 10-9rad: Beam Dynamics Resonance and Beam Position Monitors. The Spin Itself is Sensitive… • Detector Related Effects: CW vs CCW Injection, Spin Flip before Injection • Leakage Current is a Second Order Effect!
Deuterons to Flatten EV for the Muon EDM Experiment • In one single injection deuterons can probe Ev to better than a factor of ten than needed for the muon. • Inject at different radii and heights to map and shim away Ev(x,y).
Possible Further Improvement on the Muon EDM by a factor of ten: • Higher ER Fields: 8MV/m with gas to slow down free electrons. • 10 Muon Intensities under Study
Summary Electric Dipole Moment Searches: • Exciting Physics, Forefront of SUSY/Beyond SM Search. • Revolutionary New Way of Probing EDMs, Muon and Deuteron Cases-Very Exciting.
E-field Stability: Major Breakthrough Idea by Neil Shafer-Ray E-field Stability of Order 10-8 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 NP2=1016 for 10-24e.cm. Muon EDM LOI: (http://www.bnl.gov/edm) to J-PARC, <one year of running. • F. Farley et al., hep-ex/0307006