/ 99 03 44 0 v 3 4 N ov 1 99 9 The d̄ ū asymmetry of the proton in a pion cloud model approach
نویسنده
چکیده
We study the d̄ ū asymmetry of the proton in a model approach recently developed, in which hadronic fluctuations of the nucleon are generated through gluon splitting and recombination mechanisms. Within this framework, it is shown that both d̄/ū and d̄− ū distributions in the proton can be consistently described by including only nucleon fluctuations to |πN〉 and |π∆〉 bound states. Predictions of the model closely agree with the recent experimental data of the E866/NuSea Collaboration. In 1991, the New Muon Collaboration (NMC) [1] presented a determination of the non-singlet structure function F p 2 − F n 2 at Q = 4 GeV over the range 0.004 < x < 0.08. From this measurement, the Gottfried Sum Rule (GSR) [2] was estimated and a Present address: Depto. de F́ısica, Universidad de los Andes, AA 4976, Santafé de Bogotá, Colombia. e-mail: [email protected] e-mail: [email protected]
منابع مشابه
M ar 1 99 9 The d̄ − ū asymmetry of the proton in a Pion Cloud Model approach
We study the d̄− ū asymmetry of the proton in a model approach in which hadronic fluctuations of the nucleon are generated through gluon splitting and recombination mechanisms. Within this framework, it is shown that the d̄ − ū asymmetry of the proton is consistently described by including only nucleon fluctuations to |πN〉 and |π∆〉 bound states. Predictions of the model closely agree with the rec...
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