The Deuteron EDM: Experimental Aspects

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1 The Deuteron EDM: Experimental Aspects Gerco Onderwater KVI, Groningen, The Netherlands Trento June Gerco Onderwater, KVI p116

2 Outline ➀ Concept beam and spin dynamics in a electro-magnetic storage ring ➁ Implementation spin and beam preparation interaction with E-field polarimetery ➂ Statistical Uncertainty relevant experimental parameters how to optimize ➃ Systematic Uncertainty generic systematic errors spin-1 issues ➄ Conclusion Trento June Gerco Onderwater, KVI p216

3 Concept B B v v B Trento June Gerco Onderwater, KVI p316

4 Concept θ B B σ v σ v B Trento June Gerco Onderwater, KVI p316

5 Concept B vxb B σ v σ v B vxb Trento June Gerco Onderwater, KVI p316

6 Concept θ B vxb B σ v σ v B vxb Trento June Gerco Onderwater, KVI p316

7 Concept B E σ xb vxe B σ E v v B vxb Trento June Gerco Onderwater, KVI p316

8 & ) *! m T, MVm, rads ( cm, ) ( "! e Trento June Gerco Onderwater, KVI p416 A lot of math, for % " $ # "!! +-, "! :<;

9 Implementation Generic EDM Experiment consists of three parts: Beam and Spin Preparation Interaction with Electric Field Polarimetry Trento June Gerco Onderwater, KVI p16

10 Implementation POLARIZATION Zeeman effect: with RF transitions select polarization state Photo: POLIS source at KVI Trento June Gerco Onderwater, KVI p16

11 Implementation ACCELERATION Acceleration using a LINAC or cyclotron Spin is transverse during acceleration Photo: AGOR cyclotron at KVI Trento June Gerco Onderwater, KVI p16

12 Implementation SPIN ROTATION A solenoid magnet rotates the spin from vertical to horizontal, either left or right Photo: ATLAS superconducting solenoid, ANL Trento June Gerco Onderwater, KVI p16

13 Implementation INTERACTION Magnetic storage ring with magnetic quads and radial electric field Storage cycle: inject, measure, dump Photo: g 2 storage ring at BNL Trento June Gerco Onderwater, KVI p16

14 Implementation POLARIMETRY Highest efficiency from spin dependent nuclear scattering on Carbon for energy from 1 to 2 GeV Photo: EDDA polarimeter, FZJIKP Trento June Gerco Onderwater, KVI p16

15 4 ; 4 (! Statistical Uncertainty How much beamtime do we get? How many particles are in a bunch ( How long do we measure ( )? What is the initial polarization What are the efficiency? )? and analyzing power What is the strength of the electric field What is the spin coherence time What is the time constant?? in the CM? for storing the beam? Which backgrounds do we have to fit? 6 4 # 4 ( 7 7 [au] σ d T [s] τ [s] τ p [s] Trento June Gerco Onderwater, KVI p616

16 ; 4! 4 ( Statistical Uncertainty do we get? How much beamtime # ( )? How many particles are in a bunch ( )? How long do we measure (? What is the initial polarization? and analyzing power What are the efficiency 7 in the CM? What is the strength of the electric field? What is the spin coherence time for storing the beam? What is the time constant 7 Which backgrounds do we have to fit? Trento June Gerco Onderwater, KVI p616

17 4 ; 4 (! Statistical Uncertainty How much beamtime do we get? How many particles are in a bunch ( How long do we measure ( )? What is the initial polarization What are the efficiency? )? and analyzing power What is the strength of the electric field What is the spin coherence time What is the time constant?? in the CM? for storing the beam? Which backgrounds do we have to fit? 6 4 # 4 ( 7 7 Optimize: coherence: asymmetry:, number of events:, Trento June Gerco Onderwater, KVI p616

18 Extending the Coherence Time 7 Also, limit will as well will oscillate, so use RF, so that use sextupoles use Trento June Gerco Onderwater, KVI p716

19 & $ Optimizing Analyzing Power For nuclear rainbow scattering, approaches unity at large angles; cross section remains acceptable Large asymmetries also in inelastic channels, so use all charged particle:,,, He, He, Rainbow scattering expected to be most pronounced on nuclei near carbon Trento June Gerco Onderwater, KVI p16

20 Polarimeter A thin in-beam target is needed for a long beam lifetime A thick target is needed to maximize the change for a nuclear interaction Use thin target to extract the beam, and then scatter these extracted particles from a thick target This target must be the limiting aperture of the ring Efficiency of a few percent reachable, with analyzing power of about Detection Elements extraction target analyzing target BEAM Trento June Gerco Onderwater, KVI p16

21 Polarimeter A thin in-beam target is needed for a long beam lifetime A thick target is needed to maximize the change for a nuclear interaction Use thin target to extract the beam, and then scatter these extracted particles from a thick target This target must be the limiting aperture of the ring Efficiency of a few percent reachable, with analyzing power of about Detection Elements extraction target Coulomb analyzing target BEAM Nuclear Trento June Gerco Onderwater, KVI p16

22 Polarimeter A thin in-beam target is needed for a long beam lifetime A thick target is needed to maximize the change for a nuclear interaction Use thin target to extract the beam, and then scatter these extracted particles from a thick target This target must be the limiting aperture of the ring Efficiency of a few percent reachable, with analyzing power of about Detection Elements extraction target scattered particle analyzing target nuclear BEAM Coulomb Trento June Gerco Onderwater, KVI p16

23 7 ; Reachable Statistical Precission = 1 s, = 1 s, = s, 3 MVm, = 3, = 1 = 23,, = 1%,, 4 4 = 1 = 33, s, = = 1 e cm Trento June Gerco Onderwater, KVI p116

24 Guarding against Systematic Errors Many generic errors: signal spin-flip CWCCW goes as location EDM same same source const odd even const same pol rotation off axisangle const even even const different beam wobble even even const opposite beam drift non-linear PMT odd even odd odd odd even const different even even const same odd even const different NONE LOOKS LIKE AN EDM! Trento June Gerco Onderwater, KVI p1116

25 3 * Spin-1 Issues Effective Anomalous Magnetic Moment:, so, and Magnetic Quadrupole Moment: Non-zero Interacts with gradients Entrance and exit fringe fields are mirrored-symmetric; So need a precession of the spin within magnets Also, precession goes twice as fast as EDM signal Systematic errors at the level of e cm expected ( Tensor Polarization Trento June Gerco Onderwater, KVI p1216

26 Tensor Polarization and ( ( ( tensor Interaction with residual gas may lead to growing polarization (Baryshevsky) Trento June Gerco Onderwater, KVI p1316

27 Tensor Polarization and ( ( ( tensor Interaction with residual gas may lead to growing polarization (Baryshevsky) Trento June Gerco Onderwater, KVI p1316

28 Tensor Polarization and ( ( ( tensor Interaction with residual gas may lead to growing polarization (Baryshevsky) Trento June Gerco Onderwater, KVI p1316

29 Tensor Polarization and ( ( ( tensor Interaction with residual gas may lead to growing polarization (Baryshevsky) Trento June Gerco Onderwater, KVI p1316

30 Tensor Polarization and ( ( ( tensor Interaction with residual gas may lead to growing polarization (Baryshevsky) Trento June Gerco Onderwater, KVI p1316

31 Tensor Polarization and ( ( ( tensor Interaction with residual gas may lead to growing polarization (Baryshevsky) Trento June Gerco Onderwater, KVI p1316

32 Tensor Polarization and ( ( ( tensor Interaction with residual gas may lead to growing polarization (Baryshevsky) Trento June Gerco Onderwater, KVI p1316

33 Tensor Polarization and ( ( ( tensor Interaction with residual gas may lead to growing polarization (Baryshevsky) Trento June Gerco Onderwater, KVI p1316

34 Tensor Polarization and ( ( ( tensor Interaction with residual gas may lead to growing polarization (Baryshevsky) Trento June Gerco Onderwater, KVI p1316

35 ) ) Yb ) La, Sb, Other Candidates leptons: I, In*, In*, -emitters (from IB Khriplovich): Br, I, Ag*, ) Sb, Sn, Rb, ) Co, ) Na, Tb, Am ) La, Cs, Cs, Cs, Cs, Cs, Cs, Xe, Fr, ) Fr, ) Fr, ) Au, ) ) ) Hg, Au, ) ) Ta, ) Lu, Tm, ) Stable isotopes (from K Jungmann): ) ) As, Li, H, A technique with a lot of potential!! Trento June Gerco Onderwater, KVI p1416

36 Conclusions EDM measurements on charged particles seem feasible There are several methods to suppress systematic errors The deuteron looks promissing for a first experiment The deuteron spin does not make any serious problem A lot of work is being done to make a first measurement Trento June Gerco Onderwater, KVI p116

37 Suggested Reading FJM Farley, et al, "A new method of measuring electric dipole moments in storage rings", YK Semertzidis, et al, "A New Method for a Sensitive Deuteron EDM Experiment", O Lebedev, KA Olive, M Pospelov, A Ritz, "Probing CP Violation with the Deuteron Electric Dipole Moment", Contact: Gerco Onderwater <onderwater@kvinl> Trento June Gerco Onderwater, KVI p1616

A Polarimetry concept for the EDM experiment at COSY

A Polarimetry concept for the EDM experiment at COSY Paul Maanen JEDI Collaboration Physics Institute III B, RWTH Aachen University DPG Frühjahrstagung March 27, 2015 Outline Introduction Detector concept