The axial charges of proton within an extended chiral constituent quark model

Abstract

We have performed a study of the isovector, octet and singlet axial charges of the proton in an extended chiral constituent quark model, where all the possible uudq q (q = u, d, s) five-quark Fock components in the proton wave function are taken into account. The 3 P0 quark-antiquark creation mechanism is assumed to account for the transition coupling between three-and five-quark components in proton, and the corresponding transition coupling strength is fixed by fitting the intrinsic sea flavor asymmetry d − ū data for proton. Accordingly, with all the parameters fixed by empirical values, the probabilities of the intrinsic five-quark Fock components in proton wave function should be ∼ 30 − 50%, which lead to the numerical results for quark spin ∆u, ∆d and ∆s, as well the axial charges of proton consistent with the experimental data and predictions by other theoretical approaches.

The quark orbital angular momentum of ground state octet baryons

“…In addition, the experimental data for decays of baryon resonances such as ∆(1232), P 11 (1440), S 11 (1535), S 11 (1650), D 13 (1520) and D 13 (1700) [59][60][61][62][63][64] can be also well reproduced by EχCQM. Very recently, the EχCQM has been applied to study the quark OAM of the proton and flavor-dependent axial charges of the ground state octet baryons [65][66][67]. It's shown that the singlet axial charge g (0)…”