1. Hartmut Machner, MENU04 Beijing 1 Physics at COSY - up to 3.6 GeV/c - e and stochastic cooling, - stochastic extraction (10 s - min) - luminosity achieved: L = 10 32 cm -2 s -1 - p and d beams - (cooled) beam quality:  = 0.4  mm mrad (  = 0.5 mm ) ~0.1% halo at  = 2.5 mm  p/p = 5  10 -5 - close to target tracking - p vector polarised - d vector and tensor polarised

2. Hartmut Machner, MENU04 Beijing 2 Detectors: Time-of-Flight Detector TOF  K+K+ p p -- -barrel and forward scintillators -forward calorimeter -start detector -excellent tracking capability -~2 acceptance (lab)

3. Hartmut Machner, MENU04 Beijing 3 Germanium detector Detectors: Big Karl focussing spectrometer ( = 10 msr) high resolution p/p < 510 -5 combined with detectors close to target: multi-layer Germanium detector GEM

4. Hartmut Machner, MENU04 Beijing 4 Detector Systems at the Internal Beam EDDA, PISA –Non-magnetic detectors ANKE, COSY-11 –Magnetic spectrometer –COSY-11 uses a COSY dipole –ANKE: chicane with one movable dipole Employed Targets: –Strip –Cluster –Polarized Atomic (ABS) –(Pellet) EDDA COSY-11 ANKE PISA

5. Hartmut Machner, MENU04 Beijing 5 Selected topics pp pK pp pp K + K - pp  d K + K 0 (d a 0 (980)) pA  KX pd  3 He K + K - ( 3 He ) pp     strangeness production threshold production, symmetries, precision experiments p, ’ production in pp and p+d reactions  production isospin symmetry mass precision experiment pn FSI in  production

6. Hartmut Machner, MENU04 Beijing 6 Comparison to Theory

7. Hartmut Machner, MENU04 Beijing 7 Hyperon Production _ Strangeness degree of freedom: - ss creation - interaction of strange hadrons Model reconstructed  TOF p p  Y N K ( Y = ,  ) p n  Y N K K YK Y N YN Y K NK N N*N* a YN exotics TOF Exp. N*N*  N - FSI

8. Hartmut Machner, MENU04 Beijing 8 Evidence for    hyperon production:p p  p K 0  +  + (pentaquark) production: p p   +  +  p K 0  + - no acceptance cuts - complete reconstruction of final state - M = 1530  5 MeV/c 2 -   18 MeV/c 2 - large cross section:  = 0.4  0.1 stat  0.1 syst  b M. Abdel-Bary et al., Phys. Lett. B

9. Hartmut Machner, MENU04 Beijing 9  + observations

10. Hartmut Machner, MENU04 Beijing 10 ppdK + K 0 non-resonant resonant V. Yu. Grishina, EPJ

11. Hartmut Machner, MENU04 Beijing 11 pd 3 He K + K - BK acceptance beam K+K+ K-K- vertex wall 3 He p LD2 target s-wave !

12. Hartmut Machner, MENU04 Beijing 12 dp 3 He     Q=28 MeV p-wave!

13. Hartmut Machner, MENU04 Beijing 13 ss in the Nucleon  meson production p p  p p  +-0+-0 ratio R = p p  p p  p p  p p   = s s  production suppressed strangeness content of the nucleon DISTO:  (pp  pp  )/  (pp  pp  ) at fixed incident energy TOF:  (pp  pp  ) at identical excess energy R = (3  1)  10 -2 OZI rule: R = 4  10 -3 _ TOF _

14. Hartmut Machner, MENU04 Beijing 14  and ’ Production phase space + pp fsi +p fsi 3P01S0s3P01S0s 3 P 0  1 S 0 s + 1 S 0  3 P 0 s + 1 D 2  3 P 2 s importance of N* N+production!

15. Hartmut Machner, MENU04 Beijing 15 pd 3 He

16. Hartmut Machner, MENU04 Beijing 16  0 -  meson mixing + (isospin symmetric interaction) + (electromagnetic interaction) Isospin Symmetry Breaking and Quark Masses

17. Hartmut Machner, MENU04 Beijing 17 simple model for reactions close to  threshold [A. Magiera & H. Machner, NP A674(2000)515] - relative phase of and interference effect charge symmetry breaking

18. Hartmut Machner, MENU04 Beijing 18 T Isospin symmetry Magiera & Machner model=0.006±0.005 Green & Wycech (K-Matrix formalism: pd 3 He + t 3 Hepd t  = 0.010±0.005 Baru et al: strong fsi of the virtual - 3 He system Tippens et al.= 0.026±0.007

19. Hartmut Machner, MENU04 Beijing 19 pd 3 A+ -resonance with momentum dependent width Barry model

20. Hartmut Machner, MENU04 Beijing 20 Breit Wigner parametrisation reaction a (b/sr) b   (MeV) s res 1/2 (MeV) s res 1/2 -2*m p (MeV) 3 He+ 0 6.16±0.68-0.55±0.07168±203111±91234±9 3 H+ + 11.4±1.5-0.64±0.05164±253113±41236±4

21. Hartmut Machner, MENU04 Beijing 21 New determination of the -mass three reactions simultaneously: first two reactions calibrate magnetic spectrograph and beam momentum (self calibrating)

22. Hartmut Machner, MENU04 Beijing 22 result m  = 547.257  0.044 MeV/c 2

23. Hartmut Machner, MENU04 Beijing 23 Pole and continuum Boudard, Fäldt & Wilkin: works at smaller beam momenta =0 degree, pp=1640 MeV/c 100 keV resolution!

24. Hartmut Machner, MENU04 Beijing 24 pn-fsi spin triplet, isospin singlet a= +5.396 fm r 0 = 1.726 fm spin singlet, isospin triplet a= -23.678 fm r 0 = 2.51 fm

25. Hartmut Machner, MENU04 Beijing 25 pd Dynamics pd Dynamics Surprisingly large A y p in pd  (pp) s n Effect shows strong energy dependence E pp < 3 MeV p d p p n θ cm ~166 o ? pd dynamics at high momentum transfer –pd  (pp) s n –Kinematics like pd backward elastic → S-wave pp-pairs → Suppression of  –Progress –cross sections ( ) –Analyzing Power A y p ( ) –Future: Polarized target –Analyzing Power T 20 –Spin-Correlation Parameters

26. Hartmut Machner, MENU04 Beijing 26 Summary COSY has unique beam properties: emittance, resolution, polarization Instruments are complementally to each other: acceptance, resolution Convincing physics program