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Large-N_c Quark Distributions in the Delta and Chiral Logarithms in Quark Distributions of the Nucleon

Jiunn-Wei Chen·Xiangdong Ji
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Abstract

In a world with two quark flavors and a large number of colors (N_c), the polarized and unpolarized quark distributions in the delta are completely determined by those in the nucleon up to {\cal O}(1/N_c). In particular, we find q_Δ(x) =[(1\pm 2T_z)u_N(x)+ (1\mp 2T_z)d_N(x)]/2 and Δq_Δ(x) =[(5\pm 2T_z)Δu_N(x) + (5\mp 2T_z)Δd_N(x)]/10, where q = u, d and $T_z$ the charge state of a delta. The result can be used to estimate the leading chiral-logarithmic corrections to the quark distributions in the nucleon.

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Jiunn-Wei Chen, Xiangdong Ji. 2001-05-30. Large-N_c Quark Distributions in the Delta and Chiral Logarithms in Quark Distributions of the Nucleon. https://doi.org/10.1016/s0370-2693(01)01340-5

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