INT  Workshop  on

CHARGE-SYMMETRY  BREAKING
in  FEW-NUCLEON SYSTEMS



Institute for Nuclear Theory,  University of Washington,  Seattle

  October 20-22, 2003


  Organizers 

  Coordinator  


  [Part of the INT Program on Theories of Nuclear Forces and Nuclear Systems,
organized by R. Furnstahl, B. Gibson, R. Timmermans, and U. van Kolck]




Charge-symmetry breaking (CSB) in nuclear systems stems from electromagnetic effects and the up-down quark-mass difference. The latter manifests itself at the hadronic level in several guises, such as pion-nucleon seagull interactions related to the nucleon mass difference, and pi-eta mixing. Isolating these effects might lead, together with lattice simulations, to a determination of the quark-mass difference. Few-nucleon systems, where electromagnetic effects are relatively less important while data is relatively easy to come by, are the ideal ground for these explorations.

There has been a recent resurgence of interest in CSB, motivated by the TRIUMF measurement of the front-back asymmetry in p n --> d pi0 and the IUCF observation of d d --> alpha pi0. There is a need to refine our understanding of the theory of these processes.

This workshop aims at examining the various hadronic ingredients of the theory, for example:

  1. The recent experimental results on pion production: review.
  2. Pi-eta mixing and eta --> 3pi: what is known from models and from chiral perturbation theory, recent experimental results.
  3. Pion-nucleon scattering: new SCX data and existing phase-shift analyses, chiral perturbation theory.
  4. The two-nucleon system: interpretation of the data, new forces from chiral perturbation theory.
  5. COSY plans and results: pi-eta mixing from p d --> pi He/t and d d -->alpha pi0 at the eta threshold, f0-a0 mixing from pn and dd induced reactions.
  6. Other experimental possibilities: Photopion production.
  7. n p --> d pi0: existing theory.
  8. d d --> alpha pi0: first results of the theory collaboration.



    9. Attending

  9. J. Bacelar (KVI)
  10. A. Bacher (IUCF)
  11. A. Bernstein (MIT): "Experimental Opportunities to Study Quark Mass Effects in Photopion Production"
  12. A.C. Fonseca (Lisbon): "Initial-State Rescattering Contributions to d d --> alpha pi0"
  13. J.L. Friar (LANL): "How Well Do We Understand CSB in Few-Nucleon Systems?"
  14. A. Gardestig (Ohio): "d d --> alpha pi0 with Plane Waves"
  15. C. Hanhart (Juelich): "Scalar Meson Mixing in NN and dd Reactions"
    and "d d --> alpha pi0 Power Counting"
  16. E. Henley (Washington)
  17. B. Holstein (UMass): "Eta physics"
  18. C. Horowitz (Indiana)
  19. P. Kroll (Wuppertal): "Pseudoscalar Meson Mixing"
  20. A. Magiera (Jagellonian): "COSY plans/results"
  21. U.-G. Meissner (Bonn): "Status of Isospin Violation in the pi N System"
  22. G.A. Miller (Washington): "Knowns and Unknowns of CSB"
  23. F. Myhrer (South Carolina)
  24. J. Niskanen (Helsinki): "Theory of CSB n p --> d pi0"
  25. A. Nogga (INT): "d d --> alpha pi0 with a Realistic Alpha Wave-Function"
  26. A. Opper (Ohio): "Observation of CSB in n p --> d pi0 and its Implications"
  27. M.T. Pena (Lisbon): "Eta production in NN systems"
  28. M. Sadler (Abilene Christian): "New pi N data"
  29. E. Stephenson (IUCF): "Observation of the CSB d d --> alpha pi0 Reaction near Threshold"
  30. R.G.E. Timmermans (KVI)
  31. B. Tippens (DOE): "CSB in pi d --> NN eta"
  32. U. van Kolck (Arizona)

    33. (The number of participants is limited to facilitate intense discussion.)

    A tentative schedule exists.

    Note:
    The INT posts scanned transparencies of all talks presented during its programs or workshops. If you will be speaking during the workshop, please remember to submit your talk either in hardcopy or electronic format. Please see the talk submission instructions for details.



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