Photo- and electro-excitation of the Δ-resonance at MAMI

MAMI 2005

Abstract.

Over the last decade accurate experiments at MAMI played an essential role to improve our understanding of the nucleon to Δ(1232) transition. Originally to a large extent motivated through intra-quark hyperfine interactions anticipated in QCD-inspired quark models they showed that pionic degrees of freedom are essential. The meson cloud is mainly responsible for the observed quadrupole excitation strength and affects the magnetic dipole transition strength as well.

PACS.

13.60.Le Meson production 13.40.-f Electromagnetic processes and properties 14.20.Gk Baryon resonances with S = 0 

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Copyright information

© Società Italiana di Fisica and Springer-Verlag 2006

Authors and Affiliations

  1. 1.Physikalisches InstitutUniversität BonnGermany

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