https://doi.org/10.1140/epja/i2006-10043-7
Letter
Magnetic dipole moment of the Δ(1232) in chiral perturbation theory
1
Institut für Kernphysik, Johannes Gutenberg-Universität, J. J. Becher-Weg 45, D-55099, Mainz, Germany
2
High Energy Physics Institute, Tbilisi State University, Georgia
* e-mail: scherer@kph.uni-mainz.de
Received:
6
April
2006
Accepted:
7
May
2006
Published online:
1
June
2006
The magnetic dipole moment of the Δ(1232) is calculated in the framework of manifestly Lorentz-invariant baryon chiral perturbation theory in combination with the extended on-mass-shell renormalization scheme. As in the case of the nucleon, at leading order both isoscalar and isovector anomalous magnetic moments are given in terms of two low-energy constants. In contrast to the nucleon case, at next-to-leading order the isoscalar anomalous magnetic moment receives a (real) loop contribution. Moreover, due to the unstable nature of the Δ(1232), at next-to-leading order the isovector anomalous magnetic moment not only receives a real but also an imaginary loop contribution.
PACS: 12.39.Fe Chiral Lagrangians – / 13.40.Em Electric and magnetic moments – / 14.20.Gk Baryon resonances with S = 0 –
© Società Italiana di Fisica and Springer-Verlag, 2006