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Title: Dispersive approach in Sudakov resummation

Abstract

The dispersive approach to power corrections is given a precise implementation, valid beyond single gluon exchange, in the framework of Sudakov resummation for deep inelastic scattering and the Drell-Yan process. It is shown that the assumption of infrared finite Sudakov effective couplings implies the universality of the corresponding infrared fixed points. This property is closely tied to the universality of the virtual contributions to space-like and time-like processes, encapsulated in the second logarithmic derivative of the quark form factor.

Authors:
 [1]
  1. Centre de Physique Theorique, Ecole polytechnique, CNRS, 91128 Palaiseau (France)
Publication Date:
OSTI Identifier:
21056828
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 892; Journal Issue: 1; Conference: QCHS7: 7. conference on quark confinement and the hadron spectrum, Ponta Delgada, Acores (Portugal), 2-7 Sep 2006; Other Information: DOI: 10.1063/1.2714391; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CORRECTIONS; DEEP INELASTIC SCATTERING; DRELL MODEL; ELECTROMAGNETIC FORM FACTORS; GLUONS; QUARKS

Citation Formats

Grunberg, Georges. Dispersive approach in Sudakov resummation. United States: N. p., 2007. Web. doi:10.1063/1.2714391.
Grunberg, Georges. Dispersive approach in Sudakov resummation. United States. doi:10.1063/1.2714391.
Grunberg, Georges. Tue . "Dispersive approach in Sudakov resummation". United States. doi:10.1063/1.2714391.
@article{osti_21056828,
title = {Dispersive approach in Sudakov resummation},
author = {Grunberg, Georges},
abstractNote = {The dispersive approach to power corrections is given a precise implementation, valid beyond single gluon exchange, in the framework of Sudakov resummation for deep inelastic scattering and the Drell-Yan process. It is shown that the assumption of infrared finite Sudakov effective couplings implies the universality of the corresponding infrared fixed points. This property is closely tied to the universality of the virtual contributions to space-like and time-like processes, encapsulated in the second logarithmic derivative of the quark form factor.},
doi = {10.1063/1.2714391},
journal = {AIP Conference Proceedings},
number = 1,
volume = 892,
place = {United States},
year = {Tue Feb 27 00:00:00 EST 2007},
month = {Tue Feb 27 00:00:00 EST 2007}
}
  • New arguments are presented in favor of the infrared-finite coupling approach to power corrections in the context of Sudakov resummation. The more regular infrared behavior of some peculiar combinations of Sudakov anomalous dimensions, free of Landau singularities at large N{sub f}, is pointed out. A general conflict between the infrared-finite coupling and infrared renormalon approaches to power corrections is explained, and a possible resolution is proposed, which makes use of the arbitrariness of the choice of constant terms in the Sudakov exponent. Evidence for an infrared-finite perturbative effective coupling in the Drell-Yan process at large N{sub f} (albeit at oddsmore » with the infrared renormalon argument) is found within the framework of Sudakov resummation for eikonal cross sections of Laenen, Sterman and Vogelsang.« less
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  • Using the known resummation of virtual corrections together with knowledge of the leading-log structure of real radiation in a parton shower, we derive analytic expressions for the resummed real radiation after they have been integrated over all of phase space. Performing a numerical analysis for both the 13 TeV LHC and a 100 TeV pp collider, we show that resummation of the real corrections is at least as important as resummation of the virtual corrections, and that this resummation has a sizable effect for partonic center of mass energies exceeding √s=O(few TeV). For partonic center of mass energies √s≳10 TeV,more » which can be reached at a 100 TeV collider, resummation becomes an O(1) effect and needs to be included even for rough estimates of the cross-sections.« less