https://doi.org/10.1140/epja/i2006-09-010-9
MAMI 2005
Photo- and electro-excitation of the Δ-resonance at MAMI
Physikalisches Institut, Universität Bonn, Germany
* e-mail: schmieden@physik.uni-bonn.de
Received:
12
May
2006
Accepted:
12
May
2006
Published online:
15
May
2006
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 –
© Società Italiana di Fisica and Springer-Verlag, 2006
