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arXiv · 0910.1563

Electromagnetic structure of the low-lying baryons in covariant chiral perturbation theory

J. Martin Camalich·L. Alvarez-Ruso·L. S. Geng·M. J. Vicente Vacas
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Abstract

We report a calculation of the low-lying baryon magnetic moments using covariant chiral perturbation theory within the extended-on-mass-shell renormalization scheme including intermediate octet and decuplet contributions. For the case of the baryon octet, we succeed to improve the Coleman-Glashow description by including the leading SU(3)$_F$-breaking effects coming from the lowest-order loops. We compare with previous attempts at the same order using heavy-baryon and covariant infrared chiral perturbation theory, and discuss the source of the differences. For the case of the decuplet-baryons we fix the only unknown LEC with the well measured magnetic dipole moment of the $\Omega^-$ and predict the corresponding ones of the $\Delta(1232)$ isospin multiplet. In particular we obtain $\mu_{\Delta^{++}}=6.0(6) \mu_N$ and $\mu_{\Delta^{+}}=2.84(34) \mu_N$ that compare well with the current experimental information.

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J. Martin Camalich, L. Alvarez-Ruso, L. S. Geng, M. J. Vicente Vacas. 2009-10-08. Electromagnetic structure of the low-lying baryons in covariant chiral perturbation theory. https://arxiv.org/abs/0910.1563

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