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Octet magnetic moments and the Coleman-Glashow sum rule violation in the chiral quark model

Harleen Dahiya·Manmohan Gupta
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Abstract

Baryon octet magnetic moments when calculated within the chiral quark model, incorporating the orbital angular momentum as well as the quark sea contribution through the Cheng-Li mechanism, not only show improvement over the non relativistic quark model results but also gives a non zero value for the right hand side of Coleman-Glashow sum rule. When effects due to spin-spin forces between constituent quarks as well as `mass adjustments' due to confinement are added, it leads to an excellent fit for the case of p, Σ^+, Ξ^o and violation of Coleman-Glashow sum rule, whereas in almost all the other cases the results are within 5% of the data.

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Harleen Dahiya, Manmohan Gupta. 2002-08-14. Octet magnetic moments and the Coleman-Glashow sum rule violation in the chiral quark model. https://doi.org/10.1103/physrevd.66.051501

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