Exchange Currents and Nucleon Deformation

  • A. J. Buchmann
Conference paper
Part of the Few-Body Systems book series (FEWBODY, volume 11)


Information concerning the intrinsic deformation of the proton can be obtained by studying the electromagnetic p → Δ+ quadrupole transition. Recent experiments have shown that the electric quadrupole (E2) strength in γp → Δ+ is about 10 times larger than predicted by the simple quark model using only one-body currents. Our analysis provides compelling evidence for the dominance of exchange currents in the N → Δ quadrupole transition, and identifies the physical mechanism leading to the observed E2 strength.


Quadrupole Moment Charge Radius Exchange Current Charge Operator Double Spin 
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Copyright information

© Springer-Verlag 1999

Authors and Affiliations

  • A. J. Buchmann
    • 1
  1. 1.Institute for Theoretical PhysicsUniversity of TübingenTubingenGermany

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