The flavour asymmetry and quark-antiquark asymmetry in the ${\Sigma }^{+}$-sea

Abstract

The sea quark content of the ${\Sigma }^{+}$ baryon is investigated using light-cone baryon-meson fluctuation model suggested by Brodsky and Ma. It is found that the ${\Sigma }^{+}$ sea is flavour asymmetric ($\text{dbar}>\text{ubar}>\text{sbar}$) and quark-antiquark asymmetric ($q\ne \text{qbar}$). Our prediction for the flavour asymmetry, $\text{dbar}>\text{ubar}>\text{sbar}$, is significantly different from the SU(3) prediction ($\text{dbar}<\text{ubar}<\text{sbar}$), while our prediction for the $d$-$\text{dbar}$ asymmetry is consistent with the SU(3) prediction.

Comments: RevTex, 12 pages, 4 Postscript figures. The effects from the input parton distribution evolution are discussed. Conclusions remain. Version to appear in Phys. Lett. B