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The process p¯↦γπwithin the handbag approach

  • P. Kroll
  • A. Schäfer
Original Article

Abstract.

We analyse the exclusive channel p¯↦γπ0, assuming handbag dominance. The soft parts are parametrized in terms of CGLN amplitudes for the q¯↦γπ0 transition and form factors for the p¯↦q¯ ones; the latter represent moments of Generalized Distribution Amplitudes. We present a combined fit to Fermilab data from E760 taking simultaneously into account information from other exclusive reactions, especially from p¯↦γγ data. Overall a nicely consistent picture emerges, such that one can hope, that our theoretical analysis will be reliable also for the kinematics of GSI/FAIR, which, hopefully, will provide much more precise and complete data. Consequently, data from this facility should improve our knowledge both on the proton-antiproton distribution amplitudes and the pion production mechanism.

PACS.

12.38.-t Quantum chromodynamics 12.38.Bx Perturbative calculations 

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Copyright information

© Società Italiana di Fisica and Springer-Verlag 2005

Authors and Affiliations

  • P. Kroll
    • 1
  • A. Schäfer
    • 2
  1. 1.Fachbereich PhysikUniversität WuppertalWuppertalGermany
  2. 2.Institut für Theoretische PhysikUniversität RegensburgRegensburgGermany

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