Physics Program at COSY-Jülich with Polarized Hadronic Probes

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1 Mitglied der Helmholtz-Gemeinschaft Physics Program at COSY-Jülich with Polarized Hadronic Probes Forschungszentrum Jülich October 9, 2008 Andro Kacharava (JCHP/IKP, FZ-Jülich)

2 Overview COSY (Cooler Synchrotron) at Jülich (Germany) Introduction Polarized Hadrons COSY Hardware COSY Research Future Plans at COSY New Projects Hadronic probes: protons, deuterons Polarization: beams & targets Summary

3 Hadron Physics: Understanding of all matter comprised of quarks and gluons: How does Nature make hadrons? Evolution of our view of the nucleon Experimental program with polarized hadronic probes & strong theory support

4 Hadron Physics: Why Spin? Fundamental degree of freedom Crucial role in determining the basic structure of fundamental interactions Spin-dependent decays and scattering: Powerful test of theory Unique opportunity to probe the inner composite systems (e.g. proton)

COSY Facility Characteristics: 10 m Energy range: 0.045 2.8 GeV (p) 0.023 2.3 GeV (d) Max. momentum ~ 3.

5 COSY Facility Characteristics: 10 m Energy range: GeV (p) GeV (d) Max. momentum ~ 3.7 GeV/c Energy variation (ramping mode) Electron and Stochastic cooling Internal and external beams High polarization (p,d) Spin manipulation

6 Polarized Hadrons at COSY Beams: protons (p), deuterons (d) Polarized colliding-beams source: COSY ABS+cesium beam source + Lamb-shift polarimeter Targets: Hydrogen, Deuterium Polarized Internal Target (PIT): ANKE ABS + Storage Cell (SC), EDDA ABS, HERMES ABS Reaction products: N Self analysing (Λ, Σ decay) Polarimetry: Low-Energy Polarimeter (LEP) Lamb-shift Polarimeter (LSP) Breit-Rabi Polarimeter (BRP) talks: by R. Engels and A. Nass (session on Oct. 7)

COSY-Hardware (I): Polarized Internal Gas Target Main components of PIT: Atomic Beam Source (ABS) H or D H beam intensity (2 HFS) 8 10 16 atoms/s Beam size at the IP σ = 2.

7 COSY-Hardware (I): Polarized Internal Gas Target Main components of PIT: Atomic Beam Source (ABS) H or D H beam intensity (2 HFS) atoms/s Beam size at the IP σ = 2.85 ± 0.42 mm Polarization for Hydrogen P Z = 0.89 ± 0.01 P Z = ± 0.01 Lamb-Shift Polarimeter (LSP) Storage Cell (SC) in target chamber talk by R. Engels (session on Oct. 10)

TOF (beam polarization): - Non-magnetic (t-o-f) spectrometer -Extracted beam -

8 COSY- Hardware (III): Detectors ANKE ANKE (double polarization): - Magnetic spectrometer (3 dipoles) - Internal beam - (Un-), polarized target (PIT) TOF TOF (beam polarization): - Non-magnetic (t-o-f) spectrometer -Extracted beam - Large acceptance - Un- (polarized) cryo-targets ANKE and TOF: no photon detection

9 COSY- Hardware (III): Detectors WASA (beam polarization): - Internal beam - Electromagnetic calorimeter -SC solenoid - Inner and forward tracking - Pellet target (unpolarized) Charged particle and WASA photon detection Relocation from CELSIUS to COSY in 2005

10 COSY- Hardware (III): Detectors WASA (beam polarization): - Internal beam - Electromagnetic calorimeter -SC solenoid - Inner and forward tracking - Pellet target (unpolarized) Charged particle and WASA-at-COSY photon detection Commissioning in 2006 operational from 2007 on

11 COSY- Research (I): An Overview Spectroscopy, Spin, Symmetry Nuclear Forces Strangeness Symmetries In-medium Modifications Hadronic Spectroscopy (N* s, Exotics) Role of s-quark (OZI) Symmetries and Symmetry Breaking (ChS, P, C, IS) Final State Interactions (Bound States) isospin and polarization (beams, targets) as tools (final state) photons as a probe (WASA)

12 COSY- Research (II): Selected Recent Results Topics: NN-scattering Deuteron break-up Pion production η- 3 He interaction (FSI) Hyperon-Nucleon interaction Symmetry breaking

13 (1) NN Interaction

14 NN Interaction (I): The EDDA Legacy Ramping mode (E p < 2.5 GeV) Wide energy & angular range High precision, consistency for pp (I=1)-system: dσ/dω PRL 78 (1997); EPJ A 22 (2004) A N PRL 85 (2000); EPJ A 23 (2005) A ** PRL 90 (2003); PR C 71 (2005) Full characterization of elastic pp scattering (PWA) No dibaryon signal

15 NN Interaction (II): np System at ANKE np system: different isospin channel n via Charge-Exchange duteron breakup: deuteron beam: deuteron target: dp {pp} S (0 0 )+n pd {pp} S (180 0 )+n d D n p p d beam: T n up to 1.1 GeV for np d target: T p up to 2.8 GeV for pn p sp p dp observables: dσ/dω, T 20,T 22, C y,y, quasi-free np observables: A y, A yy, D yy,c xy,y, E pp < 3 MeV

16 dp (pp) n 1 S0 NN Interaction (III): np Results at ANKE Transition from deuteron to (pp)1 S 0 : pn np spin flip np spin-dependent amplitudes: dσ 2 2 2, T20, T22 γ + β, δ, ε dq Results: Method works at T n = 585 MeV Application to higher energies T d =2.23 GeV (in progress) 2 D.Chiladze et al. PLB 637, 170 (2006) New! A xx (T 22 ) A yy (T 20 ) T d = 1170 MeV T n = 585 MeV SAID np amplitudes

17 dp (pp) n 1 S0 NN Interaction (IV): np Results at ANKE Transition from deuteron to (pp)1 S 0 : pn np spin flip np spin-dependent amplitudes: dσ 2 2 2, T20, T22 γ + β, δ, ε dq Results: Method works at T n = 585 MeV Application to higher energies T d =2.23 GeV (in progress) 2 D.Chiladze et al. PLB 637, 170 (2006) dp A xx (T 22 ) A yy (T 20 ) C y,y T d = 1170 MeV Next step: Double polarized C y,y, C x,x => relative phases C x,x

18 COSY: from Pions to the Phi (2) Meson Production

19 Meson production (II): Motivation Derive chiral three-body forces from p-wave pion production Ch. Hanhart et al., PRL 85, (2000) δ π pd elastic RIKEN, KVI,... Very different kinematics, but same δ : consistency check of ChPT for NN NNπ p δ π + n 1 S 0 3 S 1 p IUCF p p Model-independent extraction from ANKE data pd p sp ppπ - p δ π - p ( 3 S 1 3 D 1 ) 1 S 0 p (unknown) Experiment is scheduled for 2009 p n Role of 4Nπ contact term

20 Meson production (III): Diproton final state Meson production: pn {pp} s X X=π (ChPT) Deuteron: bound (p+n) system, very well studied Diproton: free {pp}-pair in 1 S 0 state, E pp < 3 MeV X=(2π) (ABC effect), η X=ω, φ (OZI) By-product: Inverse diproton photodisintegration pp {pp} s γ Same kinematics as np dγ M1 multipole is forbidden New tool to study hadron interactions! Next V.Komarov et al., PRL 101(2008) PLB 661 (2008); PLB 635 (2006) Polarization observables (Ay, Ayy, Axx )

21 d+p 3 He+η: Total C.S. η- 3 He Interaction (I): (Quasi-) bound state T. Mersmann et al., PRL 98, (2007) quasi- bound state vwithin < 1MeV of threshold? Precison data, step function : nb w/i 0.5 MeV Implies large 3 Heη scattering length (~ 10 fm)

22 η- 3 He Interaction (II): (Quasi-) bound state d+p 3 He+η: Angular distr. C. Wilkin et al., PLB 654, 92 (2007) A big phase variation of the s-wave indication for a quasi-bound state? d+p 3 He+η: (analys. in progress) dσ 1 = p p η A + 2 B dω A 6 p p T 2 p = (1 2 20) pη 2 2 dσ dω 2 2 B A T20 = A + 2 B p 2 p 1 dσ B = (1 + T20) p 2 dω η asymmetry factor α α = 2 p η f Re( f s 2 + * s p C) 2 η C 2 w/ phase variation d+p 3 He+η: (next step) 2Re( A* B) = Phase determination 2 2 B between A and B C y, y 2 A η momentum p η [MeV/c]

η- 3 He Interaction (III): η-meson mass Precision data but inconsistency w/ new data!? Further investigations at COSY: d+p 3 He+η ; m~50 kev (analysis in progress) New technique!

23 η- 3 He Interaction (III): η-meson mass Precision data but inconsistency w/ new data!? Further investigations at COSY: d+p 3 He+η ; m~50 kev (analysis in progress) New technique! PLB 619 (2005) 281 GEM: SATURNE: NA48: MAMI: KLOE: CLEO: pd 3 Heη pd 3 Heη π p η n γ p η p φ η γ Ψ(2s) η J/ψ RF-induced spin-resonance: p/p ~ Barrier bucket d 1 f γ = G f 1 res 0 RF solenoid EDDA talk by M. Leonova (session on Oct. 10)

24 COSY-TOF: decay vertex (2 4) Λ (3) Strangeness DoF

25 Strangeness production (I): YN Interaction p p K + Y N (mostly COSY data) Importance of Final State Interaction PLB 649, 252 (2007): PLB 652, 245 (2007) pp pk + Λ Incoherent sum of 3 S 1 and 1 S 0 FSI with unknown relative strengths Spin dependence of FSI unknown pp pk + Σ 0 without FSI with FSI

26 Strangeness production (II): YN Interaction ΛN scattering length: singlet (a s ) and triplet (a t ) part separately Poor data base: - ΛN little known - ΣN nothing known YN scattering experiments difficult large uncertainty in Λp scattering length Theory Model-free determination in production reactions Method: dispersion relations Spin/isospin dependence TOF: high-resolution single polarized p+p K + (Λp) at (θ K,cm = 90 ) a t Theory precision is 0.3 fm A. Gasparyan et al., PRC 69, (2004) ANKE: double polarized p+n K + (Λn) (1 C NN ) σ at (θ K,cm = 0 ) a s 26

Future plans: Experiments with polarized probes 2005

27 Future plans: Experiments with polarized probes COSY proposal #152 ArXiv:nucl-ex/

28 Future plans: Exploration WASA-at-COSY Charge Symmetry Breaking (subset of isospin symmetry) E. Stephenson et al., PRL 91, (2003) Isospin violation in d+d α+π 0 d 0 + d 0 α 0 + π 1 0 Q 3.0 MeV Goal: determination of p-wave contribution at Q=60 MeV (T d =350 MeV) Pilot measurement: dd 3 He+n+π 0 (analysis in progress) most severe background channel probes the same partial waves Next step: polarized beam experiment d+d α+π 0

29 New projects: at COSY Polarized Deuterons and Protons needed to maintain and SPIN-FLIP GeV to TeV stored polarized beams talk by M. Leonova (session on Oct. 10) dedm: deuteron Electric Dipole Moment COSY task: polarimeter database and demonstration of concepts talk by Y. Semertzidis (session on Oct. 7)

30 New projects: FAIR at GSI Existing Facility HESR: Hadron Physics with Anti-Proton Beams New Part: - Atomic Physics - Nuclear Physics (RIB) - Hadron Physics - Nucleus Nucleus Coll. - Floor Plan FAIR-Facility at GSI (Darmstadt), Germany

31 New projects: HESR upgrade (Polarized Antiprotons) Method: Spin Filtering proton polarization due to multi-pass interaction with polarized targets (also works for antiprotons) talk by E. Steffens (session on Oct. 8) Physics: Transferse spin structure of the nucleon talk by M. Anselmino (session on Oct. 7) towards an asymmetric polarized antiproton-proton collider Depolarization of beams with unpolarized targets (COSY) Polarization build-up (COSY) Antiprotons (AD at CERN) talks: by F. Rathmann and A. Nass (session on Oct. 7) 31

32 Summary COSY - unique opportunities for hadron physics with polarized hadronic probes (beam & target) ANKE, TOF, WASA: state-of-the-art, complementary Physics: Spectroscopy, Spin, Symmetries selected examples and further plans at COSY Vision from COSY to: FAIR/HESR/PANDA physics with polarized antiprotons (PAX)

33 The END Thank you very much for your - attention Many thanks to the conference organizers!

General Introductory Remarks. gamardshoba. me war germaniidan CGSWHP 04. Forschungszentrum Jülich in der Helmholtz-Gemeinschaft

General Introductory Remarks. gamardshoba. me war germaniidan CGSWHP 04. Forschungszentrum Jülich in der Helmholtz-Gemeinschaft General Introductory Remarks gamardshoba me mkwia me war germaniidan me wmuschaob Hans Ströher FZ Jülich CGSWHP 04 Forschungszentrum Jülich in der Helmholtz-Gemeinschaft General Introductory Remarks CGSWHP