Header

UZH-Logo

Maintenance Infos

QCD transverse-momentum resummation in gluon fusion processes


Catani, S; Grazzini, M (2011). QCD transverse-momentum resummation in gluon fusion processes. Nuclear Physics B - Proceedings Supplements, 845(3):297-323.

Abstract

We consider the production of a generic system of non-strongly interacting particles with a high total invariant mass M in hadron collisions. We examine the transverse-momentum (q) distribution of the system in the small-q region (q≪M), and we present a study of the perturbative QCD contributions that are enhanced by powers of large logarithmic terms of the type ln(M2/qT2). These terms can be resummed to all orders in QCD perturbation theory. The partonic production mechanism of the final-state system can be controlled by quark-antiquark (qq¯) annihilation and/or by gluon fusion. The resummation formalism for the qq¯ annihilation subprocess is well established, and it is usually extrapolated to the gluon fusion subprocess. We point out that this naïve extrapolation is not correct, and we present the all-order resummation formula for the q distribution in gluon fusion processes. The gluon fusion resummation formula has a richer structure than the resummation formula in qq¯ annihilation. The additional structure originates from collinear correlations that are a specific feature of the evolution of the colliding hadrons into gluon partonic states. In the q cross section at small values of q, these gluon collinear correlations produce coherent spin correlations between the helicity states of the initial-state gluons and definite azimuthal-angle correlations between the final-state particles of the observed high-mass system.

Abstract

We consider the production of a generic system of non-strongly interacting particles with a high total invariant mass M in hadron collisions. We examine the transverse-momentum (q) distribution of the system in the small-q region (q≪M), and we present a study of the perturbative QCD contributions that are enhanced by powers of large logarithmic terms of the type ln(M2/qT2). These terms can be resummed to all orders in QCD perturbation theory. The partonic production mechanism of the final-state system can be controlled by quark-antiquark (qq¯) annihilation and/or by gluon fusion. The resummation formalism for the qq¯ annihilation subprocess is well established, and it is usually extrapolated to the gluon fusion subprocess. We point out that this naïve extrapolation is not correct, and we present the all-order resummation formula for the q distribution in gluon fusion processes. The gluon fusion resummation formula has a richer structure than the resummation formula in qq¯ annihilation. The additional structure originates from collinear correlations that are a specific feature of the evolution of the colliding hadrons into gluon partonic states. In the q cross section at small values of q, these gluon collinear correlations produce coherent spin correlations between the helicity states of the initial-state gluons and definite azimuthal-angle correlations between the final-state particles of the observed high-mass system.

Statistics

Citations

60 citations in Web of Science®
67 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

29 downloads since deposited on 19 Feb 2012
7 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Physics Institute
Dewey Decimal Classification:530 Physics
Language:English
Date:April 2011
Deposited On:19 Feb 2012 17:37
Last Modified:07 Dec 2017 11:08
Publisher:Elsevier
ISSN:0920-5632 (P) 1873-3832 (E)
Publisher DOI:https://doi.org/10.1016/j.nuclphysb.2010.12.007
Related URLs:http://arxiv.org/abs/1011.3918

Download

Download PDF  'QCD transverse-momentum resummation in gluon fusion processes'.
Preview
Content: Accepted Version
Filetype: PDF
Size: 378kB
View at publisher