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arXiv · 1003.4338

Spin 1/2^+, spin 3/2^+ and transition magnetic moments of low lying and charmed baryons

Abstract

Magnetic moments of the low lying and charmed spin 1/2^+ and spin 3/2^+ baryons have been calculated in the SU(4) chiral constituent quark model (\chiCQM) by including the contribution from c \bar c fluctuations. Explicit calculations have been carried out for the contribution coming from the valence quarks, "quark sea" polarizations and their orbital angular momentum. The implications of such a model have also been studied for magnetic moments of the low lying spin 3/2^+ \to 1/2^+ and 1/2^+ \to 1/2^+ transitions as well as the transitions involving charmed baryons. We are able to achieve an excellent agreement with data for the case of low lying spin 1/2^+ baryons and spin 3/2^+ baryons. For the spin 1/2^+ and spin 3/2^+ charmed baryon magnetic moments, our results are consistent with the predictions of the QCD sum rules, Light Cone sum rules and Spectral sum rules. For the cases where "light" quarks dominate in the valence structure, the sea and orbital contributions are found to be fairly significant however, they cancel in the right direction to give the correct magnitude of the total magnetic moment. On the other hand, when there is an excess of "heavy" quarks, the contribution of the "quark sea" is almost negligible. The effects of configuration mixing and quark masses have also been investigated.

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Neetika Sharma, Harleen Dahiya, P. K. Chatley, Manmohan Gupta. 2010-03-23. Spin 1/2^+, spin 3/2^+ and transition magnetic moments of low lying and charmed baryons. https://doi.org/10.1103/physrevd.81.073001

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