Flavor Asymmetry of the Light Quark Sea from Semi-inclusive Deep-Inelastic Scattering

Hadron Spectroscopy in the Unquenched Quark Model

“…The Gottfried sum rule has been confirmed by other experimental collaborations [30,31]. Theoretically, it was shown in Ref.…”

Quark helicity distributions from longitudinal spin asymmetries in muon–proton and muon–deuteron scattering

“…The first one is the flavour asymmetry of the light-quark sea. Unpolarised lepton scattering [2][3][4], later confirmed by DrellYan production experiments [5,6], has revealed that the light-quark difference, u − d, is negative and much larger in absolute value than expected, resulting in a large violation of the Gottfried sum rule [7]. Model calculations that explain this asymmetry also provide predictions [8][9][10] for the polarised flavour asymmetry, ∆u − ∆d.…”

Measurement of the anti-quark flavor asymmetry in the nucleon sea

“…For each prediction, the top (bottom) curve is the valence (sea) contribution and the middle curve is the sum of the two. the early measurement by NA51 which was discussed in Chapter 2 and the recent result from the HERMES collaboration [29] at DESY. Both of these measurements are in general agreement with the E866 results as seen in Fig.…”