Search for permanent Electric D ipole M oments of light ions ( , , ) in Storage Rings

1. Search for permanent Electric Dipole Moments of light ions (, , ) in Storage Rings September 18, 2012 Frank Rathmann (on behalf oftheBNL-EDMandJEDI collaborations) SPIN2012, JINR, Dubna, Russia

2. Topics • Introduction • Search forElectric Dipole Moments • Spin coherence time • First directmeasurement Resonance Method with RF E(B)-fields • Conclusion Search for permanent Electric Dipole Moments of light ions in Storage Rings

3. Whatcausedthe Baryon asymmetry? Carina Nebula: Largest-seen star-birth regions in the galaxy Whathappenedtothe antimatter? Sakharov (1967): Three conditions for baryogenesis B number conservation violated sufficiently strongly C and CP violated, B and anti-Bs with different rates Evolution of universe outside thermal equilibrium Search for permanent Electric Dipole Moments of light ions in Storage Rings

4. Electric Dipole Moments (EDMs) Permanent EDMs violate parity P and time reversal symmetry T Assuming CPT to hold, combined symmetry CP violated as well. EDMs arecandidatestosolvemysteryof matter-antimatter asymmetry  mayexplainwhywearehere! Search for permanent Electric Dipole Moments of light ions in Storage Rings

5. Historyofneutron EDM limits • Smith, Purcell, Ramsey PR 108, 120 (1957) • RAL-Sussex-ILL(dn 2.9 10-26ecm) PRL 97,131801 (2006) Adoptedfrom K. Kirch Search for permanent Electric Dipole Moments of light ions in Storage Rings

6. Limits for Electric Dipole Moments EDM searches - onlyupperlimits, in (uptonow): Hugeeffortsunderwaytoimprovelimits / find EDMs SensitivitytoNEW PHYSICS beyondthe Standard Model Search for permanent Electric Dipole Moments of light ions in Storage Rings

7. Why also EDMs of protons and deuterons? Proton anddeuteron EDM experimentsmayprovideone order highersensitivity. In particularthedeuteronmayprovide a muchhighersensitivitythanprotons. • Consensus in the theoretical community: • Essential to perform EDM measurements on different targets with similar sensitivity: • unfold the underlying physics, • explain the baryogenesis. Search for permanent Electric Dipole Moments of light ions in Storage Rings

8. Search for Electric Dipole Moments NEW: EDM search in time developmentofspinin a storage ring: “Freeze“ horizontal spinprecession; watch fordevelopmentof a verticalcomponent! Search for permanent Electric Dipole Moments of light ions in Storage Rings

9. Search for Electric Dipole Moments NEW: EDM search in time developmentofspinin a storage ring: “Freeze“ horizontal spinprecession; watch fordevelopmentof a verticalcomponent! A magicstorage ring forprotons (electrostatic), deuterons, … Onemachinewithm Search for permanent Electric Dipole Moments of light ions in Storage Rings

10. Twostorage ring projectsbeingpursued Jülich, focus on deuterons, or a combinedmachine BNL forprotons all electricmachine CW and CCW propagatingbeams (from A. Lehrach) (fromR. Talman) Search for permanent Electric Dipole Moments of light ions in Storage Rings

11. Most recent: Richard Talmansconceptfor a Jülich all-in-onemachine Iron-free, current-only, magnetic bending, eliminates hysteresis B A B A Search for permanent Electric Dipole Moments of light ions in Storage Rings

12. BNL Proposal 2 beamssimultaneouslyrotating in an all electricring (cw, ccw) ApprovedBNL-Proposal Submittedto DOEGoal forprotons Circumference Technological challenges ! • Spin coherence time • Beam positioning • Continuouspolarimetry • E - fieldgradients Carry out proofofprincipleexperiments (demonstrators) atCOSY Search for permanent Electric Dipole Moments of light ions in Storage Rings

13. The frozen spin Method Fortransverseelectricandmagneticfields in a ring ( ), anomalousspin precession isdescribedby x Magic condition: Spin alongmomentumvector Foranysignof, in a combinedelectricandmagneticmachine For(protons) in an all electric ring (magic) Search for permanent Electric Dipole Moments of light ions in Storage Rings

14. Magic condition: Protons Case 1: fieldonly Search for permanent Electric Dipole Moments of light ions in Storage Rings

15. Parameters for Jülich all-in-onemachine(R. Talmansconcept) Talman/Gebel givemaximumachievablefieldofcoppermagnetsof ~ 0.15 T. • Fitting such a machineintothe COSY buildingfavorslowermomenta. Search for permanent Electric Dipole Moments of light ions in Storage Rings

16. EDM at COSY –COolerSYnchrotron Cooler andstorage ring for (polarized) protonsanddeuterons Phase space cooledinternal & extractedbeams COSY … the spin-physics machine for hadron physics Injector cyclotron Search for permanent Electric Dipole Moments of light ions in Storage Rings

17. EDM at COSY –COolerSYnchrotron Cooler andstorage ring for (polarized) protonsanddeuterons Phase space cooledinternal & extractedbeams COSY … an ideal starting point for a srEDM search Injector cyclotron Search for permanent Electric Dipole Moments of light ions in Storage Rings

18. “spin closed orbit vector” makes one turn “spin tune” if ║ ring stable polarization A Spin closedorbit one particle with magnetic moment Search for permanent Electric Dipole Moments of light ions in Storage Rings

19. Spin coherence Weusuallydon‘tworryaboutcoherenceofspinsalong Polarization not affected! Atinjection all spinvectorsaligned (coherent) After some time, spinvectorsget out ofphaseandfullypopulatethecone Situation very different, whenyou deal with Longitudinal polarizationvanishes! In an EDM machinewithfrozenspin, observation time is limited. Atinjection all spinvectorsaligned After some time, thespinvectorsare all out ofphaseand in the horizontal plane Search for permanent Electric Dipole Moments of light ions in Storage Rings

20. Estimateofspincoherencetimes (N.N. Nikolaev) Onesourceofspincoherencearerandomvariationsofthespin tune due tothemomentumspread in the beam and israndomizedby e.g., electroncooling Estimate: Spin coherence time fordeuteronsmaybelarger thanforprotons Search for permanent Electric Dipole Moments of light ions in Storage Rings

21. First measurementofspincoherence time 2011 Test measurementsat COSY Polarimetry: Spin coherence time: decoherence time oscillation capture from Ed Stephenson and Greta Guidoboni Search for permanent Electric Dipole Moments of light ions in Storage Rings

22. Topics • Introduction • Search forElectric Dipole Moments • Spin coherence time • First directmeasurement Resonance Method with RF E(B)-fields • Conclusion Search for permanent Electric Dipole Moments of light ions in Storage Rings

23. ResonanceMethodwith „magic“ RF Wien filter Avoidscoherent betatron oscillationsof beam. Radial RF-E andvertical RF-B fieldstoobservespinrotation due to EDM Approach pursuedfor a firstdirectmeasurementat COSY.  „Magic RF Wien Filter“ no Lorentz force IndirectEDM effect Tiltofprecession plane due to EDM RF E(B)-field In-plane polarization Observable: Accumulationofverticalpolarizationduringspincoherence time stored d Polarimeter (dpelastic) • Statistical sensitivityfor in therange torangepossible. • Alignmentandfieldstabilityof ring magnets • Imperfectionof RF-E(B) flipper Search for permanent Electric Dipole Moments of light ions in Storage Rings

24. Operation of „magic“ RF Wien filter Radial E andvertical B fieldsoscillate, e.g., with(here). beam energy Spin coherence time maydepend on excitationand on chosenharmonics Search for permanent Electric Dipole Moments of light ions in Storage Rings

25. Simulation ofresonanceMethod with „magic“ Wien filterfordeuteronsat COSY Parameters: beam energy assumed EDM E-field Linear extrapolationoffor a time periodof Preliminary, based on K. Nikolaevsderivationofthecombinedrotationmatricesof E/B flipperand ring EDM effectaccumulates in . Search for permanent Electric Dipole Moments of light ions in Storage Rings

26. Simulation ofresonanceMethod with „magic“ Wien filterfordeuteronsat COSY Parameters: beam energy assumed EDM E-field Linear extrapolationoffor a time periodof. EDM effectaccumulates in Search for permanent Electric Dipole Moments of light ions in Storage Rings

27. Simulation ofresonanceMethod with Magic Wien filterfordeuteronsat COSY Parameters: beam energy assumed EDM E-field Linear extrapolationoffor a time periodof. EDM effectaccumulates in Search for permanent Electric Dipole Moments of light ions in Storage Rings

28. Technicallydriventimelineforall-electricpEDMat BNL 15 18 12 13 14 16 17 19 20 21 Two years R&D/preparation One year final ring design Two years ring/beam-line construction Two years installation One year “string test” Search for permanent Electric Dipole Moments of light ions in Storage Rings

29. Stepwiseapproachfor all-in-onemachinefor JEDI Time scale:Steps 1 and 2: < 5 years Steps 3 and 4: > 5 years Search for permanent Electric Dipole Moments of light ions in Storage Rings

30. srEDM cooperations International srEDM Network Institutional (MoU) and Personal (Spokespersons …) Cooperation, Coordination srEDMCollaboration (BNL) (spokespersonYannisSemertzidis) JEDI Collaboration (FZJ)(spokespersons: A. Lehrach, J. Pretz, F.R.) • Common R&D • RHICEDM-at-COSY • Beam Position Monitors Polarimetry • (…) Spin Coherence Time • Cooling • Spin Tracking (…) Study Group First directmeasurement Ring Design DOE-Proposal(submitted) CD0, 1, … HGF Application(s) pEDM Ring at BNL JEDI Search for permanent Electric Dipole Moments of light ions in Storage Rings

31. Summary • Measurementsof EDMs areextremelydifficult, but thephysicsisfantastic! • Twostorage ring projects, at BNL and Jülich • All-in-onemachinewithcopper-onlymagnets • Pursuespincoherence time measurementsatCOSY • First directEDM measurementat COSY Resonance Method with RF E(B) -fields • JEDI collaborationestablished Search for permanent Electric Dipole Moments of light ions in Storage Rings

32. “Man mußetwasNeuesmachen, um etwasNeueszusehen.” “You have to make (create) something new, if you want to see something new” Georg Christoph Lichtenberg (1742-1799) Search for permanent Electric Dipole Moments of light ions in Storage Rings

33. Spares Search for permanent Electric Dipole Moments of light ions in Storage Rings

34. Magic condition: Protons Case 2: and fields magicenergy magicenergy Search for permanent Electric Dipole Moments of light ions in Storage Rings

35. Magic condition: Deuterons and fields Search for permanent Electric Dipole Moments of light ions in Storage Rings

36. Magic condition: Helions and fields Search for permanent Electric Dipole Moments of light ions in Storage Rings

37. Some polarimetry issues • srEDMexperimentsusefrozenspinmode, i.e., beam mostlypolarizedalongdirectionofmotion, • most promising ring optionsusecw & ccwbeams. • scattering on C destructive on beam andphase-space, • scatteringon C determinespolarizationofmainlyparticleswith large betatron amplitudes, and • is not capabletodetermine . • Forelasticscattering longitudinal analyzingpowersaretiny (violatesparity). Ideally, use a methodthatwoulddetermine. pCanddC polarimetry isthecurrentlyfavoredapproachforthepEDMexperimentat BNL Search for permanent Electric Dipole Moments of light ions in Storage Rings

38. Exploit observables thatdepend onbeam andtargetpolarization Spin-dependent differential crosssectionfor Analyzing power Spin correlations In scattering, necessary observables are well-knownin therangeMeV (not so foror). Search for permanent Electric Dipole Moments of light ions in Storage Rings

39. How couldone do that, determine? Detector CW CCW cell • Detector determinesofcw & ccwbeamsseparately, based on kinematics. • Alignmentoftargetpolarization along axesbymagneticfields. Leads tounwanted MDM rotations absolute no-goin EDM experiments. Suggestion 1: Use a polarizedstoragecelltarget Search for permanent Electric Dipole Moments of light ions in Storage Rings

40. How couldone do that, determine? Detector Polarizedionsource(~10 MeV) • Collidetwoexternalbeamswithcwandccwstoredbeams. • Energycouldbetunedtomatchdetectoracceptance. • Polarizationcomponentsofprobinglow-energy beam canbemadelarge, wouldbeselectedbyspinrotators in thetransmissionlines. • Luminosityestimatesnecessary Suggestion 2: Usecolliding beam fromexternalsource Search for permanent Electric Dipole Moments of light ions in Storage Rings

41. How couldone do that, determine? Detector CW CCW • Requiresluminosity, -functionsat IP shouldberathersmall. • Advantage oversuggestion 2. isthatsupportsluminosity. • Disadvantageisthatsensitivitycomesmainlyfromtermswithand. • Detailedestimatesnecessary. Suggestion 3: Usedirectlyreactionsfromcollidingbeams Search for permanent Electric Dipole Moments of light ions in Storage Rings

42. Luminosityestimateforthecollideroption Conditions: Even undertheseveryoptimisticassumptions, event rate will beratherlow. Search for permanent Electric Dipole Moments of light ions in Storage Rings

43. ResonanceMethodwith RF E-fields spin precession governedby: (* restframe) verticalpolarization RF E-field • Two situations: •  EDM effect •  no EDM effect stored d Polarimeter (dpelastic) • This way, the EDM signalisaccumulatedduringthecycle. • Statistical improvementoversingle turn effectisabout: . • Brings us in therangefor. • But: Flippingfields will leadtocoherent betatron oscillations, withhardto handle systematics. Search for permanent Electric Dipole Moments of light ions in Storage Rings

44. Simulation ofresonanceMethodwith RF E-fieldsfordeuteronsat COSY Parameters: beam energy assumed EDM E-field E-fieldreversedevery Constant E-field Numberofturns Numberofturns Search for permanent Electric Dipole Moments of light ions in Storage Rings

45. Simulation ofresonanceMethodwith RF E-fieldsfordeuteronsat COSY Parameters: beam energy assumed EDM E-field Linear extrapolationoffor a time periodof EDM effectaccumulates Polarimeter determines Numberofturns Search for permanent Electric Dipole Moments of light ions in Storage Rings

46. Symmetries Physical laws are invariant under certain transformations. • T-Symmetry: C-parity(or Charge parity): • Changessignof all quantizedcharges • electrical charge, • baryon number, • lepton number, • flavor charges, • Isospin (3rd-component) Parity: Search for permanent Electric Dipole Moments of light ions in Storage Rings

47. EDM Workshop at ECT* (Trento) October 1-5, 2012 http://www.ectstar.eu/ • Organizingcommittee • Jülich • Hans Ströher h.stroeher@fz-juelich.de • Frank Rathmann f.rathmann@fz-juelich.de • Andreas Wirzbaa.wirzba@fz-juelich.de • Brookhaven • Mei Baimbai@bnl.gov • William Marciano marciano@bnl.gov • Yannis Semertzidis yannis@bnl.gov Search for permanent Electric Dipole Moments of light ions in Storage Rings