Abstract In this letter, we investigate the nucleon quasi-parton distribution functions in the chiral quark soliton model. We derive a set of sum-rules depending on the velocity of the nucleon and on the Dirac matrix defining the distribution functions. We present numerical results for the isosinglet unpolarized distribution, in which we find that the anti-quark distribution breaks the positivity condition at nucleon velocities of v ≈ 0.99 ( P N ≈ 7.0 M N ) and smaller. We found that, for the isosinglet unpolarized case, a large nucleon momentum is required for the quasi-parton distribution to get close enough to the usual parton distribution function.

中文翻译：

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大 N 极限中的核子准子分布

摘要 在这封信中，我们研究了手征夸克孤子模型中的核子准子分布函数。我们根据核子的速度和定义分布函数的狄拉克矩阵推导出一组求和规则。我们给出了等单线非极化分布的数值结果，其中我们发现反夸克分布在 v ≈ 0.99 ( PN ≈ 7.0 MN ) 或更小的核子速度下打破了正性条件。我们发现，对于等单波非极化情况，准子分布需要大的核子动量才能足够接近通常的子分布函数。