Helicity-dependent distribution of strange quarks in the proton from nonlocal chiral effective theory

Centre Authors: Thomas, A. W., Wang, X.

The helicity-dependent strange quark distribution in the proton, Δs, is calculated in a nonlocal chiral SU(3) effective field theory. The hadronic proton to meson plus octet or decuplet baryon splitting functions are derived at the one-loop level, with loop integrals rendered finite by correlation functions introduced in the nonlocal Lagrangian. Within the convolution framework, the proton strange helicity distribution is obtained using spin-flavor symmetry to constrain the input valence quark distributions in the hadronic intermediate states. The polarized strange quark distribution is found to be quite small, with the lowest moment of Δs negative, but consistent with recent global QCD analyses.

Published: May, 2022

DOI: http://dx.doi.org/10.1103/physrevd.105.094007