Inclusive and diffractive structure functions at small x

详细信息	查看全文 | 推荐本文 |

• 作者：Buchmü ; ller ; W. ; Gehrmann ; T. ; Hebecker ; A.
• 关键词：13.60.Hb ; 11.15.Kc ; 11.80.Fv ; 12.38.Bx ; Diffraction ; Structure function ; Small x ; Semiclassical ; Eikonal ; Wilson line
• 刊名：Nuclear Physics B
• 出版年：1999
• 期刊代码：45_05503213
• 类别：ph
• 出版时间：January 4, 1999
• 卷：537
• 期：1-3
• 页码：477-500
• 文件大小：1.04 M

摘要

In the semiclassical approach, inclusive and diffractive quark and gluon distributions are expressed in terms of correlation functions of Wilson loops. Each Wilson loop integrates the colour field strength in the area between the trajectories of two fast partons penetrating the proton. We introduce a specific model for averaging over the relevant colour field configurations. Within this model, all parton distributions at some low scale Q²₀ are given in terms of three parameters. Inclusive and diffractive structure functions at higher values of Q² are determined in a leading-order QCD analysis. In both cases, the evolution is driven by a large gluon distribution. A satisfactory description of the structure functions F₂(x,Q²) and F^D(3)₂ (ξ,β,Q²) is obtained. The observed rise of F^D(3)₂ with ξ is parametrized by a non-perturbative logarithmic energy dependence, compatible with unitarity. In our analysis, the observed rise of F₂ at small x is largely due to the same effect.