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Magnetic dipole moment of the $Δ(1232)$ in chiral perturbation theory

C. Hacker·N. Wies·J. Gegelia·S. Scherer
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Abstract

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.

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C. Hacker, N. Wies, J. Gegelia, S. Scherer. 2006-03-31. Magnetic dipole moment of the $Δ(1232)$ in chiral perturbation theory. https://doi.org/10.1140/epja%2Fi2006-10043-7

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