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Title: Global fit to scattering data with next-to-leading logarithmic BFKL resummations

Abstract

We calculate deep inelastic scattering (DIS) scheme splitting and coefficient functions for electromagnetic DIS with small x resummations, as given by the next-to-leading-logarithmic Balitsky-Fadin-Kuraev-Lipatov (NLL BFKL) equation with running coupling and approximate NLL resummed impact factors. The resummations are combined with a next-to-leading order (NLO) fixed-order expansion, and the improved quantities thus obtained are stable at small x and significantly suppressed with respect to leading logarithmic (LL) results. These results are implemented in a global fit to DIS and related data, and the results compared to a NLO fixed-order DIS scheme fit and with a previous LL resummed fit. The NLL resummed fit quality is excellent and constitutes a marked improvement over the purely fixed-order approach. The input gluon, at Q{sub 0}{sup 2}=1 GeV{sup 2}, obtained from the resummed fit is positive and slightly increasing as x{yields}0, in contrast to the result obtained at fixed order. A resummed prediction for the longitudinal structure function F{sub L} is presented. It is positive definite and growing with energy at low x and Q{sup 2}, where the fixed-order results show a significant perturbative instability.

Authors:
 [1];  [2]
  1. NIKHEF, Kruislaan 409, 1098 SJ Amsterdam (Netherlands)
  2. Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT (United Kingdom)
Publication Date:
OSTI Identifier:
21010981
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevD.75.034005; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COUPLING; DEEP INELASTIC SCATTERING; ELECTROMAGNETIC INTERACTIONS; FOUR MOMENTUM TRANSFER; GLUONS; PARTICLE KINEMATICS; PERTURBATION THEORY; QUANTUM CHROMODYNAMICS; STRUCTURE FUNCTIONS

Citation Formats

White, C. D., and Thorne, R. S.. Global fit to scattering data with next-to-leading logarithmic BFKL resummations. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.034005.
White, C. D., & Thorne, R. S.. Global fit to scattering data with next-to-leading logarithmic BFKL resummations. United States. doi:10.1103/PHYSREVD.75.034005.
White, C. D., and Thorne, R. S.. Thu . "Global fit to scattering data with next-to-leading logarithmic BFKL resummations". United States. doi:10.1103/PHYSREVD.75.034005.
@article{osti_21010981,
title = {Global fit to scattering data with next-to-leading logarithmic BFKL resummations},
author = {White, C. D. and Thorne, R. S.},
abstractNote = {We calculate deep inelastic scattering (DIS) scheme splitting and coefficient functions for electromagnetic DIS with small x resummations, as given by the next-to-leading-logarithmic Balitsky-Fadin-Kuraev-Lipatov (NLL BFKL) equation with running coupling and approximate NLL resummed impact factors. The resummations are combined with a next-to-leading order (NLO) fixed-order expansion, and the improved quantities thus obtained are stable at small x and significantly suppressed with respect to leading logarithmic (LL) results. These results are implemented in a global fit to DIS and related data, and the results compared to a NLO fixed-order DIS scheme fit and with a previous LL resummed fit. The NLL resummed fit quality is excellent and constitutes a marked improvement over the purely fixed-order approach. The input gluon, at Q{sub 0}{sup 2}=1 GeV{sup 2}, obtained from the resummed fit is positive and slightly increasing as x{yields}0, in contrast to the result obtained at fixed order. A resummed prediction for the longitudinal structure function F{sub L} is presented. It is positive definite and growing with energy at low x and Q{sup 2}, where the fixed-order results show a significant perturbative instability.},
doi = {10.1103/PHYSREVD.75.034005},
journal = {Physical Review. D, Particles Fields},
number = 3,
volume = 75,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}
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