EDM of the muon, deuteron, and proton in storage rings

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1 EDM of the muon, deuteron, and proton in storage rings William Morse BNL W.Morse - BNL 1

2 Storage Ring EDM Collaboration Aristotle University of Thessaloniki, Thessaloniki/Greece (3) 21 Institutions 80 Collaborators Research Inst. for Nuclear Problems, Belarusian State University, Minsk/Belarus (1) Brookhaven National Laboratory, NY/USA (27) Budker Institute for Nuclear Physics, Novosibirsk/Russia (5) University College, London/UK (1) Cornell University, Ithaca, NY/USA (4) Institut für Kernphysik and Jülich Centre for Hadron Physics Forschungszentrum Jülich, Jülich/Germany (10) Institute of Nuclear Physics Demokritos, Athens/Greece (3) University and INFN Ferrara, Ferrara/Italy (1) Laboratori Nazionali di Frascati dell'infn, Frascati/Italy (3) Joint Institute for Nuclear Research, Dubna/Russia (1) Indiana University, Indiana/USA (2) Istanbul Technical University, Istanbul/Turkey (2) University of Groningen, KVI, Groningen/The Netherlands (3) University of Massachusetts, Amherst, Massachusetts/USA (1) Michigan State University, East Lansing, Minnesota/USA (2) Dipartimento do Fisica, Universita Tor Vergata and Sezione INFN, Rome/Italy(3) University of Patras, Patras/Greece (5) Regis University, Denver, Colorado/USA (1) CEA, Saclay, Paris/France (1) University of Virginia, Virginia/USA (1) W.Morse - BNL 2

3 Spin Precession ds B * d E dt * * W.Morse - BNL 3

4 EDM Permanent edm violates P and T symmetries. Field started by Norman Ramsey et al. in the 1950s. Sensitive searches have been done so far only on neutral systems: neutron, atoms, etc. W.Morse - BNL 4

5 Neutron EDM Limit vs. Year 1.E+06 10^-26 e-cm 1.E+04 1.E+02 1.E Year W.Morse - BNL 5

6 W.Morse - BNL 6 Spin Precession in Storage Ring MDM g a mc S ge E g B a S mc e dt S d T 1 2 ˆ ˆ

7 Focusing Electric Quadrupoles W.Morse - BNL 7

8 Muon g-2 Experiment Data W.Morse - BNL 8

9 Standard Model Predictions SM MDM: a = (5) BNL Exp: a = (6) 3 difference. New Physics? Upgraded a experiments proposed at FNAL and JPARC. BNL experiment: d < ecm. W.Morse - BNL 9

10 Dedicated EDM Experiment? Started thinking about a dedicated muon edm experiment in the late 1990s. SM EDM d e-cm. Just have to worry about our experimental error, as SM theory error is effectively nil. Also, SM gives effectively nil Baryon Asymmetry of the Universe so new T violating physics is needed. What about systematic errors? Use symmetries CW/CCW and SP W.Morse - BNL 10

11 W.Morse - BNL 11 Spin Precession in Storage Ring ˆ ˆ E g B a S mc e dt S d T B E d dt S d

12 Frozen MDM S_x/S_z Precession edm = 10^-29 ecm 2.E E S_y frozen S_y/ S 0.E+00 0 S_x/ S S_y not frozen S_x frozen -1.E S_x not frozen -2.E t (s) W.Morse - BNL 12

13 CW/CCW Flips EDM Signal edm = 10^-29 ecm 2.E E S_y frozen S_y/ S 0.E+00 0 S_x/ S S_y not frozen S_x frozen -1.E S_x not frozen -2.E t (s) W.Morse - BNL 13

14 Freeze MDM Precession Radial Bending Electric Field = Part a (s) K.E. (GeV) abc a E R (MV/m) B V (T) stat /10 7 s (ecm) muon D P W.Morse - BNL 14

15 Deuteron E/B R 0 = 8.4m W.Morse - BNL 15

16 Pedm: only E, one beam channel W.Morse - BNL 16

17 3m long Tevatron pbar-p Separator W.Morse - BNL 17

18 Magic proton ring lattice: ~25m radius I.K.: Injection Kickers P: Polarimeters RF: RF-system S: Sextupoles Q: Quadrupoles BPMs: ~70 Beam Position Monitors W.Morse - BNL 18

19 Proton Statistical Error: d p 3 E AP N ft R c Tot p : p 103 s Polarization Lifetime (Spin Coherence Time) A : 0.6 Left/right asymmetry observed by the polarimeter P : 0.8 Beam polarization N c : p/cycle Total number of stored particles per cycle T Tot : 10 7 s Total running time per year f : 0.5% Useful event rate fraction (efficiency for EDM) E R : 17 MV/m Radial electric field strength (65% azim. cov.) d p ecm/year W.Morse - BNL 19

20 Proton or Deuteron? BNL has space for PEDM ring, and is working on a site specific design. COSY has space for DEDM ring, and is thinking about it. R&D proceeding by SREDM collaboration on both. I will now give details of PEDM W.Morse - BNL 20

21 SR EDM R&D Teamleaders Precision Polarimetry Ed Stephenson, IUCF High Electric Field WM, BNL. Long Spin Coherence Time Gerco Onderwater, KVI. Precise Beam Position Monitors for control of the main spin systematics Dave Kawall, U. Mass. Beam-beam effects, etc. Alexei Fedotov, BNL. Lattice Richard Talman, Cornell. W.Morse - BNL 21

22 ½ of PEDM Polarimeter W.Morse - BNL 22

23 P Magic Energy: 232 MeV W.Morse - BNL 23

24 Storage Ring EDM Technical Review 12/7/2009 Polarimeter Development Requirements 1. Measure a change in the vertical polarization with a sensitivity of Provide a continuous record with time. Reduce systematic errors to below the sensitivity limit. 2. Track the magnitude of the polarization with time. 3. Provide transverse (X) asymmetry data continuously for control. Operate at high efficiency. Development proposal made to COSY-Jülich in Ring design was for 1 GeV/c deuteron beam (250 MeV) Best scheme requires deuteron scattering from carbon. Conduct study using as much existing equipment as possible. (Begin studies of production/preservation of horizontal polarization.) Deuteron and proton polarimeters are similar. W.Morse - BNL 24 Edward J. Stephenson, IUCF 1

25 White noise extraction COSY ring: Polarimeter Development at COSY Julich, Germany EDDA detector:. Use EDDA detector Tube target, extracts along inside edge with white noise. W.Morse - BNL 25

26 Polarimeter Systematic Errors Cross ratio sensitive to S y (t) to first order: CR = (r - 1)/(r + 1) r 2 = L + R - /L - R + Index ratio sensitive to polarimeter acceptance to first order: IR = (s - 1)/(s + 1) s 2 = L + L - /R - R + W.Morse - BNL 26

27 Polarimeter Systematic Errors <10-29 ecm Cross Ratio L/R theta x Index L/R theta x x (mm) or theta (mrad) x (mm) or theta (mrad) W.Morse - BNL 27

28 As High Bending E-field as Possible The field emission without and with high pressure water rinsing (HPR) for 0.5cm plate separation. Recent developments from Cornell, JLab ERL R&D W.Morse - BNL 28

29 Spin Coherence Time with Longitudinally Polarized Beams 1s due mainly to beam (dp/p) 2 Add sextupoles with radial E field or vertical B field x 2 -y 2. at locations with large x, y, and D. Set correctly to better than one part in R&D plan to show this works at COSY. W.Morse - BNL 29

30 Spin Systematics for Electric Focusing <B r > 2 pg, for ecm. <F y > = e<e y + cb r > = 0 <E y > = <cb r > Earth s <B r > 0, since BNL is not close to the north or south poles. W.Morse - BNL 30

31 Spin Systematics for Electric Focusing Trust but verify: <B r > will split the CW/CCW beams vertically: <y> CW = - <y> CCW = R<B r >/(cn) Focusing field index n = (R de y /dy)/e r Measure with BPMs and correct. W.Morse - BNL 31

32 Required averaged CW/CCW difference resolution 1.E-06 1.E-05 <y>_cw - <y> _ccw resolution (m) 1.E-07 1.E-08 1.E-09 1.E-10 1.E-11 1.E-12 1.E-06 1.E-07 1.E-08 1.E-09 1.E-10 1.E-11 <B_r> resolution (G) 1.E-13 1.E-06 1.E-04 1.E-02 1.E+00 1.E+02 1.E+04 1.E+06 1.E-12 time (s) W.Morse - BNL 32

33 Resonant Cavity BPM W.Morse - BNL 33

34 Dipole TM 110 Mode Measures: (Iy) CW -(Iy) CCW If y CW = y CCW = y, then Second order: (I CW -I CCW ) y Data taken with: B r cos( br t) splits the cw-ccw beams. E v cos( ev t) moves both cw-ccw beams together. Frequency Hz. Calculating finite beam size effects, etc. W.Morse - BNL 34

35 Image electric field will be different if Q CW Q CCW W.Morse - BNL 35

36 Systematics for Magnetic Focusing Problem is not a radial magnetic field, but a vertical electric field that is different CW/CCW. Two beams are not at the same height CW/CCW at the pm level. CW(CCW) beam heights determined by F(D) quads. Need resolution of <1pm averaged over 10 7 s. Similar required bpm resolution as for electric focusing! Decide at May collaboration meeting at BNL. W.Morse - BNL 36

37 Conclusions EDM = Extremely Difficult Experiment Martin Cooper New idea: Precision measurements of charged particle edms. Passed BNL technical review December CD0 type TDR in W.Morse - BNL 37

38 Extras W.Morse - BNL 38

39 Magic Proton EDM ring includes: Injection Bunch capture with RF Vertical to horizontal spin precession Slow extraction onto an internal target for polarization monitoring Use RF-feedback from polarimeter to keep spin longitudinal W.Morse - BNL 39

conservation) implies CPviolation, which is needed to

40 Electric Dipole Moments: P and T-violating when d // to spin q g s, 2m q d s 2mc T-violation (under CPT conservation) implies CPviolation, which is needed to explain why matter W.Morse - BNL 40 is dominating over anti-matter in our universe

41 Storage Ring EDM Technical Review 12/7/2009 Polarimeter Development Polarimeter Properties Broad acceptance for high efficiency: Angle range = 5 to ~20 Excitation range < ~40 MeV No particle identification Stable properties rely on stable gains, thresholds, etc. Build and calibrate (including systematic errors properties) Implications for polarimeter design: Low analyzing power particles can be removed with an absorber Count everything above threshold DAQ can be simple (scaler) and fast for high statistics, low dead time Detector must be insensitive to rate changes Thick targets are required (several cm) for high efficiency (~1%) Design features that go beyond current polarimeters: Extraction from a storage ring onto a thick internal target Reduction of systematic error effects to 10 6 W.Morse - BNL 41 Edward J. Stephenson, IUCF 3

42 Storage Ring EDM Technical Review 12/7/2009 COSY ring: Polarimeter Development COSY tests EDDA detector: Rings and bars to determine angles. Use EDDA detector LEFT UP DOWN RIGHT Azimuthal angles yield two asymmetries: W.Morse - BNL 42 Edward J. Stephenson, IUCF 4 EDM L L R R g2 D U D U

43 Storage Ring EDM Technical Review 12/7/2009 Polarimeter Development Target Concept Target solution found at COSY: expanded vertical phase space beam core White noise applied to electric field plates. 15 mm maximum allowed at COSY end view Do enough particles penetrate far enough into the front face to travel most of the way through the target? This requires a comparison of the efficiency with model values. W.Morse - BNL 43 Edward J. Stephenson, IUCF 5

44 Storage Ring EDM Technical Review 12/7/2009 Polarimeter Development Systematic Error Effects Goal: keep errors in change of asymmetry to less than Things can change: geometry rate Use standard tricks r 1 2 L( ) R( ) pa r + L + R r 1 L( ) R( ) (good to first order in the errors) Correct effects arising at higher order Try to use detector information: correction parameters Geometry: Rate: L R s s s L( ) L( ) R( ) R( ) (instantaneous rate) This requires a calibration of sensitivity to systematic errors. Will this work? W.Morse - BNL 44 Edward J. Stephenson, IUCF 7

Storage Ring EDM Technical Review 12/7/2009 Polarimeter Development Polarimeter (Half) Polarimeter in the ring: Quadrupoles here are larger aperture for clearance.

45 Storage Ring EDM Technical Review 12/7/2009 Polarimeter Development Polarimeter (Half) Polarimeter in the ring: Quadrupoles here are larger aperture for clearance. 5 to 20 acceptance Absorber to remove low analyzing power particles. (Detector choice can also give discrimination.) One target is shown. We want a target available from at least the left, right, up and down directions. cm Generic detector: (?) Multi-resistive plate chamber (?) Micro-megas (?) Gas electron multiplier Equal rate readout pads Rate = 800 /s/pad (?) other W.Morse - BNL In one store: 45 Edward J. Stephenson, IUCF 15 4

46 From the September 2008 run Polarimeter team at COSY Resonance crossing using RF-solenoid (full spin flip) Vector asymmetry V+ T Unp V T+ Slowly extracting the beam while monitoring its polarization as a function of time W.Morse - BNL 46

Storage ring Electric Dipole Moment experiment for the proton Yannis K. Semertzidis, BNL

Lattice Computations BNL, 16 May 2012 Storage ring Electric Dipole Moment experiment for the proton Yannis K. Semertzidis, BNL Goal: 10-29 e cm; Probe New Physics ~10 3 TeV Systematics best in an all-electric