ar X iv : h ep - p h / 02 06 30 3 v 1 2 8 Ju n 20 02 PACS Classification : DRAFT Double logarithms , ln 2 ( 1 / x
نویسنده
چکیده
Theoretical predictions show that at low values of Bjorken x the spin structure function is influenced by large logarithmic corrections, ln(1/x), which may be predominant in this region. These corrections are also partially contained in the NLO part of the standard DGLAP evolution. Here we calculate the non-singlet component of the nucleon structure function, g 1 = g 1 − g 1 , and its first moment, using a unified evolution equation. This equation incorporates the terms describing the NLO DGLAP evolution and the terms which contribute to the ln(1/x) resummation. In order to avoid double counting in the overlapping regions of the phase-space, a unique way of including the NLO terms into the unified evolution equation is proposed. The scheme-independent results obtained from this unified evolution are compared to the NLO fit to experimental data, GRSV’2000. Analysis of the first moments of g 1 confirms that the unified evolution including the ln(1/x) resummation goes beyond the NLO DGLAP analysis. Corrections generated by double logarithms at low x influence strongly the Q-dependence of the first moments.
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Theoretical predictions show that at low values of Bjorken x the spin structure function, g1 is influenced by large logarithmic corrections, ln (1/x), which may be predominant in this region. These corrections are also partially contained in the NLO part of the standard DGLAP evolution. Here we calculate the non-singlet component of the nucleon structure function, g 1 = g 1 − g 1 , and its firs...
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