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arXiv · hep-ph/0406135

The spread of the gluon k_t-distribution and the determination of the saturation scale at hadron colliders in resummed NLL BFKL

Abstract

The transverse momentum distribution of soft hadrons and jets that accompany central hard-scattering production at hadron colliders is of great importance, since it has a direct bearing on the ability to separate new physics signals from Standard Model backgrounds. We compare the predictions for the gluonic k_t-distribution using two different approaches: resummed NLL BFKL and DGLAP evolution. We find that as long as the initial and final virtualities (k_t) along the emission chain are not too close to each other, the NLL resummed BFKL results do not differ significantly from those obtained using standard DGLAP evolution. The saturation momentum Q_s(x), calculated within the resummed BFKL approach, grows with 1/x even slower than in the leading-order DGLAP case.

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BibTeXRIS

V. A. Khoze, A. D. Martin, M. G. Ryskin, W. J. Stirling. 2004-07-05. The spread of the gluon k_t-distribution and the determination of the saturation scale at hadron colliders in resummed NLL BFKL. https://doi.org/10.1103/physrevd.70.074013

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