Catani Stefano, de Florian Daniel, Rodrigo Germán, Vogelsang Werner
INFN, Sezione di Firenze and Dipartimento di Fisica, Università di Firenze, I-50019 Sesto Fiorentino, Florence, Italy.
Phys Rev Lett. 2004 Oct 8;93(15):152003. doi: 10.1103/PhysRevLett.93.152003.
We point out that perturbative evolution in QCD at three loops generates a strange-antistrange asymmetry s(x) - s(x) in the nucleon's sea just from the fact that the nucleon has nonvanishing up and down quark valence densities. The recently computed three-loop splitting functions allow for an estimate of this effect. We find that a fairly sizable asymmetry may be generated. Results for analogous asymmetries in the heavy-quark sector are also presented.
我们指出，在 QCD 中三圈的微扰演化仅由于核子具有非零的上夸克和下夸克价密度，就在核子海产生了奇异 - 反奇异不对称性 s(x) - s(x)。最近计算出的三圈分裂函数使得能够对这种效应进行估计。我们发现可能会产生相当大的不对称性。还给出了重夸克领域类似不对称性的结果。
