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arXiv · 0912.4494

Unquenched quark model for baryons: magnetic moments, spins and orbital angular momenta

R. Bijker·E. Santopinto
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Abstract

We present an unquenched quark model for baryons in which the effects of the quark-antiquark pairs (up, down and strange) are taken into account in an explicit form via a microscopic, QCD-inspired, quark-antiquark creation mechanism. In the present approach, the contribution of the quark-antiquark pairs can be studied for any inital baryon and for any flavor of the pairs. It is shown that, while the inclusion of quark-antiquark pairs does not affect the baryon magnetic moments, it leads to a sizeable contribution of the orbital angular momentum to the spin of the proton and the Lambda hyperon.

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R. Bijker, E. Santopinto. 2009-12-22. Unquenched quark model for baryons: magnetic moments, spins and orbital angular momenta. https://doi.org/10.1103/physrevc.80.065210

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