The method of regions and next-to-soft corrections in Drell-Yan production

D. Bonocore; E. Laenen; L. Magnea; L. Vernazza; C. D. White

doi:10.1016/j.physletb.2015.02.008

The method of regions and next-to-soft corrections in Drell-Yan production

D. Bonocore
, E. Laenen
, L. Magnea
, L. Vernazza
, C. D. White^*

^*Corresponding author for this work

Research output: Contribution to journal › Article › Academic › peer-review

Abstract

We perform a case study of the behaviour of gluon radiation beyond the soft approximation, using as an example the Drell-Yan production cross section at NNLO. We draw a careful distinction between the eikonal expansion, which is in powers of the soft gluon energies, and the expansion in powers of the threshold variable 1 - z, which involves important hard-collinear effects. Focusing on the contribution to the NNLO Drell-Yan K-factor arising from real-virtual interference, we use the method of regions to classify all relevant contributions up to next-to-leading power in the threshold expansion. With this method, we reproduce the exact two-loop result to the required accuracy, including z-independent non-logarithmic contributions, and we precisely identify the origin of the soft-collinear interference which breaks simple soft-gluon factorisationat next-to-eikonal level. Our results pave the way for the development of a general factorisation formula for next-to-leading-power threshold logarithms, and clarify the nature of loop corrections to a set of recently proposed next-to-soft theorems. (C) 2015 The Authors. Published by Elsevier B.V.

Original language	English
Pages (from-to)	375-382
Number of pages	8
Journal	Physics Letters B
Volume	742
DOIs	https://doi.org/10.1016/j.physletb.2015.02.008
Publication status	Published - 6 Mar 2015

Funding

We thank Babis Anastasiou, Pietro Falgari, Einan Gardi, Duff Neill and Marco Volponi for useful discussions and correspondence. This work was supported by the Research Executive Agency (REA) of the European Union through the contracts PITN-GA-2010-264564 (LHCPhenoNet) and PITN-GA-2012-316704 (HIGGS-TOOLS), by MIUR (Italy), under contract 2010YJ2NYW_006, and by the University of Torino and the Compagnia di San Paolo under contract ORTO11TPXK. D.B. and E.L. have been supported by the Netherlands Foundation for Fundamental Research on Matter (FOM) programme 104, "Theoretical Particle Physics in the Era of the LHC", and by the Netherlands Organisation for Scientific Research (NWO). C.D.W. is supported by the UK Science and Technology Facilities Council (STFC). We are grateful to the Higgs Centre for Theoretical Physics at the University of Edinburgh, where part of this work was carried out, for warm hospitality. E.L. thanks the Galileo Galilei Institute for Theoretical Physics for hospitality, and the INFN for partial support during the completion of this work. L.M., L.V. and C.D.W. thank Nikhef for hospitality and support during the completion of this work.

Keywords

LEPTON-PAIR PRODUCTION
HIGGS-BOSON
LARGE-X
ASYMPTOTIC-EXPANSION
FEYNMAN-INTEGRALS
CROSS-SECTIONS
GLUON-FUSION
K-FACTOR
RESUMMATION
QCD

Access to Document

10.1016/j.physletb.2015.02.008

1-s2.0-S0370269315000702-mainFinal published version, 590 KB

Cite this

@article{20d4ab76257646a5a5ca66ab75db3f24,

title = "The method of regions and next-to-soft corrections in Drell-Yan production",

abstract = "We perform a case study of the behaviour of gluon radiation beyond the soft approximation, using as an example the Drell-Yan production cross section at NNLO. We draw a careful distinction between the eikonal expansion, which is in powers of the soft gluon energies, and the expansion in powers of the threshold variable 1 - z, which involves important hard-collinear effects. Focusing on the contribution to the NNLO Drell-Yan K-factor arising from real-virtual interference, we use the method of regions to classify all relevant contributions up to next-to-leading power in the threshold expansion. With this method, we reproduce the exact two-loop result to the required accuracy, including z-independent non-logarithmic contributions, and we precisely identify the origin of the soft-collinear interference which breaks simple soft-gluon factorisationat next-to-eikonal level. Our results pave the way for the development of a general factorisation formula for next-to-leading-power threshold logarithms, and clarify the nature of loop corrections to a set of recently proposed next-to-soft theorems. (C) 2015 The Authors. Published by Elsevier B.V.",

keywords = "LEPTON-PAIR PRODUCTION, HIGGS-BOSON, LARGE-X, ASYMPTOTIC-EXPANSION, FEYNMAN-INTEGRALS, CROSS-SECTIONS, GLUON-FUSION, K-FACTOR, RESUMMATION, QCD",

author = "D. Bonocore and E. Laenen and L. Magnea and L. Vernazza and White, \{C. D.\}",

year = "2015",

month = mar,

day = "6",

doi = "10.1016/j.physletb.2015.02.008",

language = "English",

volume = "742",

pages = "375--382",

journal = "Physics Letters B",

issn = "0370-2693",

publisher = "Elsevier BV",

}

TY - JOUR

T1 - The method of regions and next-to-soft corrections in Drell-Yan production

AU - Bonocore, D.

AU - Laenen, E.

AU - Magnea, L.

AU - Vernazza, L.

AU - White, C. D.

PY - 2015/3/6

Y1 - 2015/3/6

N2 - We perform a case study of the behaviour of gluon radiation beyond the soft approximation, using as an example the Drell-Yan production cross section at NNLO. We draw a careful distinction between the eikonal expansion, which is in powers of the soft gluon energies, and the expansion in powers of the threshold variable 1 - z, which involves important hard-collinear effects. Focusing on the contribution to the NNLO Drell-Yan K-factor arising from real-virtual interference, we use the method of regions to classify all relevant contributions up to next-to-leading power in the threshold expansion. With this method, we reproduce the exact two-loop result to the required accuracy, including z-independent non-logarithmic contributions, and we precisely identify the origin of the soft-collinear interference which breaks simple soft-gluon factorisationat next-to-eikonal level. Our results pave the way for the development of a general factorisation formula for next-to-leading-power threshold logarithms, and clarify the nature of loop corrections to a set of recently proposed next-to-soft theorems. (C) 2015 The Authors. Published by Elsevier B.V.

AB - We perform a case study of the behaviour of gluon radiation beyond the soft approximation, using as an example the Drell-Yan production cross section at NNLO. We draw a careful distinction between the eikonal expansion, which is in powers of the soft gluon energies, and the expansion in powers of the threshold variable 1 - z, which involves important hard-collinear effects. Focusing on the contribution to the NNLO Drell-Yan K-factor arising from real-virtual interference, we use the method of regions to classify all relevant contributions up to next-to-leading power in the threshold expansion. With this method, we reproduce the exact two-loop result to the required accuracy, including z-independent non-logarithmic contributions, and we precisely identify the origin of the soft-collinear interference which breaks simple soft-gluon factorisationat next-to-eikonal level. Our results pave the way for the development of a general factorisation formula for next-to-leading-power threshold logarithms, and clarify the nature of loop corrections to a set of recently proposed next-to-soft theorems. (C) 2015 The Authors. Published by Elsevier B.V.

KW - LEPTON-PAIR PRODUCTION

KW - HIGGS-BOSON

KW - LARGE-X

KW - ASYMPTOTIC-EXPANSION

KW - FEYNMAN-INTEGRALS

KW - CROSS-SECTIONS

KW - GLUON-FUSION

KW - K-FACTOR

KW - RESUMMATION

KW - QCD

U2 - 10.1016/j.physletb.2015.02.008

DO - 10.1016/j.physletb.2015.02.008

M3 - Article

SN - 0370-2693

VL - 742

SP - 375

EP - 382

JO - Physics Letters B

JF - Physics Letters B

ER -

The method of regions and next-to-soft corrections in Drell-Yan production

Abstract

Funding

Keywords

Access to Document

Fingerprint

Cite this