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New Opportunities for Hadron Physics with the Planned PANDA Detector

New Opportunities for Hadron Physics with the Planned PANDA Detector. Overview of the PANDA Physics Program The PANDA Detector Selected Simulation Results Charmonium: EM decays Charmonium: Open charm decays Charmonium in nuclear matter. Why don‘t we observe isolated quarks?

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New Opportunities for Hadron Physics with the Planned PANDA Detector

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  1. New Opportunities for Hadron Physics with the Planned PANDA Detector • Overview of the PANDA Physics Program • The PANDA Detector • Selected Simulation Results • Charmonium: EM decays • Charmonium: Open charm decays • Charmonium in nuclear matter James Ritman Univ. Giessen

  2. Why don‘t we observe isolated quarks? • Q-Q potential in the charmonium system • Are there other forms of hadrons? e.g. Hybrids qqg or Glueballs gg • Why are hadrons so much heavier than their constituents? • p-A interactions What Do We Want To Know? James Ritman Univ. Giessen

  3. Why Don’t We See Isolated Quarks? James Ritman Univ. Giessen

  4. Charmonium – the Positronium of QCD • Charmonium • Positronium Mass [MeV] Binding energy [meV] 4100 y ¢¢¢ (4040) Ionisationsenergie P (~ 3940) 3 2 0 3900 D 3 (~ 3800) P (~ 3880) 3 3 D 3 S 3 S 3 1 3 3 3 D 1 2 1 0 1 2 3 D P (~ 3800) D 3 -1000 3 1 1 y ¢¢ (3770) 0 2 D 2 P 3 3 D 2 P 3 D 3 3 2 1 2 2 S 3 2 2 S 1 1 1 2 P 1 3 Threshold ¢ ~ 600 meV 0 y (3686) 3700 1 2 P 3 0 10-4 eV h ¢ (3590) -3000 c c (3556) 2 h (3525) c c (3510) 1 3500 c (3415) 0 -5000 3300 1 S 3 8·10-4 eV 1 S 1 1 0 -7000 y (3097) 3100 0.1 nm + - e e C 1 fm h (2980) C c 2900 James Ritman Univ. Giessen

  5. In pp annihilation all mesons can be formed Resonance cross section Measured rate Beam CM Energy Why Antiprotons? • e+e- annihilation via virtual photon: only states with Jpc = 1-- • Resolution of the mass and width is only limited by the beam momentum resolution James Ritman Univ. Giessen

  6. High Resolution • Crystal Ball: typical resolution ~ 10 MeV • Fermilab: 240 keV  p/p < 10-4 needed James Ritman Univ. Giessen

  7. Open Questions c (11S0) (Simu results)experimental error on M > 1 MeVG hard to understand in simple quark models c’ (21S0) Crystal Ball result way off study of hadronic decays hc(1P1) Spin dependence of QQ potential Compare to triplet P-States LQCD  NRQCD James Ritman Univ. Giessen

  8. Open Questions States above the DD threshold Higher vector states not confirmed Y(3S), Y(4S) Expected location of 1st radial excitation of P wave statesExpected location of narrow D wave states Only Y(3770) seenSensitive to long range Spin-dependent potential (Simu results) James Ritman Univ. Giessen

  9. Why Are Hadrons So Heavy? James Ritman Univ. Giessen

  10. Hadron Masses 2Mu + Md ~ 15 MeV/c2 Mp = 938 MeV/c2 Protons = (uud) ? no low mass hadrons (except p, K, h) spontaneously broken chiral symmetry (P.Kienle)

  11. u u u u u u d d d d d d d d d d d d Hadron Production in the Nuclear Medium Mass of particles may change in dense matter  Quark atom _ D+ d c attractive _ d c D- repulsive James Ritman Univ. Giessen

  12. J/Y Absorption in Nuclei J/Y absorption cross section in nuclear matter p + A  J/Y + (A-1) (Simu results)

  13. Comparison of p-A Reactions to A-A Much lower momentum for heavy producedparticles (2 GeV for “free”)(Effects are smaller at high momentum) Well defined nuclear environment (T and r) James Ritman Univ. Giessen

  14. The Experimental Facility James Ritman Univ. Giessen

  15. HESR

  16. HESR: High Energy Storage Ring Beam Momentum 1.5 - 15 GeV/c High Intensity Mode: Luminosity 2x1032 cm-2s-1 (2x107Hz) dp/p (st. cooling) ~10-4 High Resolution Mode: Luminosity 2x1031 cm-2s-1 dp/p (e- cooling) ~10-5 James Ritman Univ. Giessen

  17. James Ritman Univ. Giessen

  18. James Ritman Univ. Giessen

  19. Central Tracking Detectors • Straw-Tubes • Mini-Drift-Chambers • MVD: (Si) 5 layers • ~ 9 Mio pixels • Andrei Sokolov HK39.5 Thursday 15:00

  20. PID • ToF • Muon Detectors • DIRC (DIRC@BaBar) James Ritman Univ. Giessen

  21. Open Charm pp DD DKpp „no backgroundevents added“ Mass Resolution ~ 10 MeV/c2 James Ritman Univ. Giessen

  22. Longitudinal Scale up by x10! 0.15 < Vz < 5 mm signal DPM background Vertex Distributions GEANT4 Transverse D meson signal DPM background James Ritman Univ. Giessen

  23. DD Missing Mass signal DPM background N.B. different x scale | Mmiss2|< 0.001 GeV2 (tight cut) James Ritman Univ. Giessen

  24. Open Charm As an example of the Pbar P  Y(3770)  DD Analysis Plot MDD – MD – MD + 2x1869MeV raw S/B ~ 10-7 James Ritman Univ. Giessen

  25. Detection of Rare Neutral Channels As an example: hcggBackground: p0g, p0p0 hc:p0g:p0p0 1:50:500 Comparison with E835 (PLB 566,45) PANDA James Ritman Univ. Giessen

  26. Dimuon Spectrum in p+Cu • Beam momentum “on resonance” • Full background simulations (result scaled up) • Muons from J/Y have high Pt • J/Y has low Pt (coplanar) J/Y James Ritman Univ. Giessen

  27. Summary • GSI will explore the intensity frontier • High luminosity cooled p from 1-15 GeV/c • Wide physics program including • Charmonium spectroscopy • pbar-A reactions • Search for glueballs and charm hybrids James Ritman Univ. Giessen

  28. James Ritman Univ. Giessen

  29. In part supported by: GSI BMBF 06GI144 DFG James Ritman Univ. Giessen

  30. Target • A fiber/wire target will be needed for D physics, • A pellet target is conceived: • 1016 atoms/cm2 for D=20-40mm 1 mm James Ritman Univ. Giessen

  31. Electromagnetic Calorimeter James Ritman Univ. Giessen

  32. Example reaction: pp  J/y + F (s = 4.4 GeV/c2) Tracking Resolution Single track resolution Invariant mass resolution J/y  m+m- F K+K- s(J/y) = 35 MeV/c2 s(F) = 3.8 MeV/c2 James Ritman Univ. Giessen

  33. Staged Construction James Ritman Univ. Giessen

  34. Pbar-Nucleus Interactions The interaction of charmed mesons with the baryonic environment strongly effects production rates near threshold James Ritman Univ. Giessen

  35. p _ X 3GeV/c X- Strange Baryons in Nuclear Fields Hypernuclei open a 3rd dimension (strangeness) in the nuclear chart • Double-hypernuclei:very little data • Baryon-baryon interactions:L-N only short ranged (no 1p exchange due to isospin) L-L impossible in scattering reactions K+K Trigger secondary target • X-(dss)p(uud)L(uds)L(uds)

  36. _ Probe large separations with highly excited qq states Charmonium Spectroscopy James Ritman Univ. Giessen

  37. The GSI Future Project • Nuclear Structure: • paths of nucleo-synthesis • Heavy Ion Physics: • hot and dense nuclear matter • Ion and laser induced Plasma: • very high energy densities • Atomic physics: • QED, strong EM fields, Ion-Matter interactions • Physics with Antiprotons • properties of the strong force Project approved Feb 2003 James Ritman Univ. Giessen

  38. Open Questions • The c(11S0) • The c(21S0) • The hc(1P1) • States above the DD threshold James Ritman Univ. Giessen

  39. Proton Form Factors at large Q2 At high values of momentum transfer |Q2| the system should be describable by perturbative QCD. Due to dimensional scaling, the FF should vary as Q4. The time like FF remains about a factor 2 above the space like. These differences should vanish in pQCD, thus the asymptotic behavior has not yet been reached at these large values of |q2|. (HESR up to s ~ 25 GeV2) q2>0 q2<0 James Ritman Univ. Giessen

  40. Mixing With Mesonic States Width: could be narrow (5-50 MeV) since DD suppressed for some states O+- DD,D*D*,DsDs (CP-Inv.) (QQg)  (Qq)L=0+(Qq)L=0 (Dynamic Selection Rule) If DD forbidden, then the preferred decay is (ccg)  (cc) + X , e.g. 1-+  c + h James Ritman Univ. Giessen

  41. Spontaneous Breaking of Chiral Symmetry Although the QCD Lagrangian is symmetric, the ground state need not be. (e.g. Fe below TCurie ) Example:

  42. Exotic Hadrons James Ritman Univ. Giessen

  43. g g g Glueballs C. Morningstar PRD60, 034509 (1999) Self interaction between gluons  Construction of color-neutral hadrons with gluons possible exotic glueballs don‘t mix with mesons (qq) 0--, 0+-, 1-+, 2+-, 3-+,... James Ritman Univ. Giessen

  44. Charm Hybrids ccg Prediction in QCD: Collective gluon excitation (Gluons contribute to quantum numbers) Ground state: JPC = 1-+ (spin exotic) distance between quarks James Ritman Univ. Giessen

  45. Partial Wave Analysis Partial wave analysis as important tool Example of 1-+(CB@LEAR) pd  X(1-+)+p+p, X  h p Strength ~ qq States ! Signal in production but not in formation is interesting ! James Ritman Univ. Giessen

  46. The QCD vacuum is not empty Hadron masses are generated by the strong interaction with <qq> (also with gluon condensate) Quark Condensate The density of the quark condensate will change as a function of temperature and density in nuclei. This should lead to modifications of the hadron’s spectral properties. James Ritman Univ. Giessen

  47. Hadrons in the Nuclear Medium Reduction of <qq> Spectral functions <qq> S.Klimt et al., Nucl. Phys. A515, 429 (1990). W.Peters et al., Nucl. Phys. A632, 109 (1998).

  48. Deeply Bound Pionic Atoms Pionic capture is possible with the appropriate choice of kinematics: d+n  3He + p- These results indicate a mass shift of ~25 MeV for pions at normal nuclear matter density. James Ritman Univ. Giessen

  49. Kaons in Nuclear Matter Kaon and anti-kaon masses should no longer be degenerate in nuclear matter. Expected signal: increased K- production compared to K+. J.Schaffner-Bielich et al., Nucl. Phys. A (1997) 325. James Ritman Univ. Giessen

  50. Measured K- Cross Section Comparison of proton-proton data with heavy ion data[2]: dramatic enhancement of the K- production probability KaoS [1] A.Sibirtsev et al., Z.Phys. A358 (1997) 101. [2] F.Laue et al., Phys.Rev. Lett. 82 (1999) 1640. [3] C.Quentmeier et al., Phys Lett B 515 (2001) 276. James Ritman Univ. Giessen

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