Do we expect light flavor sea - quark asymmetry also for the spin - dependent distribution functions of the nucleon ?
نویسندگان
چکیده
After taking account of the scale dependence by means of the standard DGLAP evolution equation, the theoretical predictions of the chiral quark soliton model for the unpolarized and longitudinally polarized structure functions of the nucleon are compared with the recent high energy data. The theory is shown to explain all the qualitative features of the experiments, including the NMC data for F p 2 (x) − Fn 2 (x), Fn 2 (x)/F p 2 (x), the Hermes and NuSea data for d̄(x) − ū(x), the EMC and SMC data for g 1(x), gn 1 (x) and gd 1(x). Among others, flavor asymmetry of the longitudinally polarized sea-quark distributions is a remarkable prediction of this model, i.e., it predicts that ∆d̄(x)−∆ū(x) = C xα[d̄(x)− ū(x)] with a sizable negative coefficient C ' −2.0 (and α ' 0.12) in qualitative consistency with the recent semi-phenomenological analysis by Morii and Yamanishi. Email : [email protected] Email : [email protected]
منابع مشابه
Light flavor sea-quark asymmetry for the spin-dependent distribution functions of the nucleon
The theoretical predictions of the chiral quark soliton model for the unpolarized and longitudinally polarized structure functions of the nucleon are compared with recent high energy data. The theory is shown to explain all the qualitatively noticeable features of the existing experiments, including the light flavor sea-quark asymmetry for the unpolarized distribution functions established by t...
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