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arXiv · hep-ph/0303253

Spin Studies of Nucleons in a Statistical Model

J. P. Singh·Alka Upadhyay
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Abstract

We decompose various quark-gluon Fock states of a nucleon in a set of states in which each of the three-quark core and the rest of the stuff, termed as a sea, appears with definite spin and color quantum number, their weight being determined, statistically, from their multiplicities. The expansion coefficients in the quark-gluon Fock states have been taken from a recently proposed statistical model. We have also considered two modifications of this model with a view to reduce the contributions of the sea components with higher multiplicities. With certain approximations, we have calculated the quark contributions to the spin of the nucleon,the ratio of the magnetic moments of nucleons, their weak decay constant, and the ratio of SU(3) reduced matrix elements for the axial current. A reasonably close agreement with the corresponding experimental values have been obtained in all the three cases.

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J. P. Singh, Alka Upadhyay. 2003-03-30. Spin Studies of Nucleons in a Statistical Model. https://doi.org/10.1088/0954-3899%2F30%2F7%2F005

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