An estimate of higher twist at small $x_{mathrmB}$ and low $Q^2$ based upon a Saturation Model
An estimate of higher twist at small $x_{mathrmB}$ and low $Q^2$ based upon a Saturation Model
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基于饱和模型对小 $x_{mathrmB}$ 和低 $Q^2$ 处较高扭曲的估计
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
K. Peters
中科院分区：
文献类型：
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作者：
Jochen Bartels;Krzysztof Golec;K. Peters
抽象。我们研究了在低Q^2和小x HERA区域中，高扭转修正对深部非弹性结构函数的影响。我们回顾了在小x下导致扭曲4的最低阶QCD图的一般特征，特别是纵向和横向结构函数的符号结构，它提供了F_2 $中强相消的可能性。对于数值分析，我们进行了扭曲分析的饱和模型已非常成功的描述在HERA的结构功能和DIS衍射截面。作为主要结论，在$F_L$或$F_T$中，扭转4修正量不小，但在$F_2=F_L + F_T$中，它们几乎相互抵消。这表明在小x和$Q^2$的情况下使用DG形式主义的局限性。我们指出，F_L分析需要一个大的扭转4修正。我们还指出了扭转展开的有效区域。
Abstract. We investigate the influence of higher twist corrections to deep inelastic structure functions in the low-$Q^2$ and small-x HERA region. We review the general features of the lowest-order QCD diagrams which contribute to twist-4 at small-x, in particular the sign structure of longitudinal and transverse structure functions which offers the possibility of strong cancellations in $F_2$. For a numerical analysis we perform a twist analysis of the saturation model which has been very successful both in describing the structure function and the DIS diffractive cross section at HERA. As the main conclusion, twist 4 corrections are not small in $F_L$ or $F_T$ but in $F_2=F_L + F_T$ they almost cancel. This indicates the limitation on the use of the DGLAP formalism at small x and $Q^2$. We point out that $F_L$ analysis needs a large twist-4 correction. We also indicate the region of validity of the twist expansion.