Difference between the u- and d- sea quark distributions in the proton was first observed in the violation of the Gottfried sum rule in deep-inelastic scattering (DIS) experiments. The parton momentum fraction x dependence of this difference has been measured over the region 0.02. <. x<. 0.35 from Drell-Yan and semi-inclusive DIS experiments. The Drell-Yan data suggested a possible sign-change for d-(x)-u-(x) near x~. 0.3, which has not yet been explained by existing theoretical models. We present an independent evidence for the d-(x)-u-(x) sign-change at x~. 0.3 from an analysis of the DIS data. We further discuss the x-dependence of d--u- in the context of meson cloud model and the lattice QCD formulation.
|Number of pages||4|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|State||Published - Sep 7 2014|
Bibliographical noteFunding Information:
The authors would like to acknowledge University of Malaysia Sabah for the Collaborative Research Grant Scheme Award.
- Lattice QCD
- Parton distributions
- Sea quark
ASJC Scopus subject areas
- Nuclear and High Energy Physics