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A Statistical Treatment to the Evolution Equation for Quark Distributions

Hai Lin
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Abstract

The evolution of polarized quark distribution functions is taken into account the gluon emission and absorption, quark pair production and annihilation processes and treated by a statistical method which provides quark distribution functions at small $Q^2$. The evolution function of quark distributions is derived and solved by numerical methods. Then the $Q^2$ dependent and $α_{s}$ dependent structure functions $F_{2}(x, Q^{2})$ are obtained and the example of it, the proton structure function, is calculated, whose increase and decrease tendency with $α_{s}$ at different $x$ is consistent with experiments. This is also an evidence that the statistical methods for the nucleon is reasonable.

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Hai Lin. 2001-06-11. A Statistical Treatment to the Evolution Equation for Quark Distributions. https://arxiv.org/abs/hep-ph/0106100

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