Direct Extraction of Oneloop Integral Coefficients
Abstract
We present a general procedure for obtaining the coefficients of the scalar bubble and triangle integral functions of oneloop amplitudes. Coefficients are extracted by considering twoparticle and triple unitarity cuts of the corresponding bubble and triangle integral functions. After choosing a specific parameterization of the cut loop momentum we can uniquely identify the coefficients of the desired integral functions simply by examining the behavior of the cut integrand as the unconstrained parameters of the cut loop momentum approach infinity. In this way we can produce compact forms for scalar integral coefficients. Applications of this method are presented for both QCD and electroweak processes, including an alternative form for the recently computed threemass triangle coefficient in the sixphoton amplitude A{sub 6}(1{sup }, 2{sup +}, 3{sup }, 4{sup +}, 5{sup }, 6{sup +}). The direct nature of this extraction procedure allows for a very straightforward automation of the procedure.
 Authors:
 Publication Date:
 Research Org.:
 Stanford Linear Accelerator Center (SLAC)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 902482
 Report Number(s):
 SLACPUB12455
arXiv:0704.1835; TRN: US200717%%354
 DOE Contract Number:
 AC0276SF00515
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review D
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AMPLITUDES; AUTOMATION; BUBBLES; QUANTUM CHROMODYNAMICS; SCALARS; UNITARITY; PhenomenologyHEP,HEPPH, HEPTH
Citation Formats
Forde, Darren. Direct Extraction of Oneloop Integral Coefficients. United States: N. p., 2007.
Web. doi:10.1103/PhysRevD.75.125019.
Forde, Darren. Direct Extraction of Oneloop Integral Coefficients. United States. doi:10.1103/PhysRevD.75.125019.
Forde, Darren. Mon .
"Direct Extraction of Oneloop Integral Coefficients". United States.
doi:10.1103/PhysRevD.75.125019. https://www.osti.gov/servlets/purl/902482.
@article{osti_902482,
title = {Direct Extraction of Oneloop Integral Coefficients},
author = {Forde, Darren},
abstractNote = {We present a general procedure for obtaining the coefficients of the scalar bubble and triangle integral functions of oneloop amplitudes. Coefficients are extracted by considering twoparticle and triple unitarity cuts of the corresponding bubble and triangle integral functions. After choosing a specific parameterization of the cut loop momentum we can uniquely identify the coefficients of the desired integral functions simply by examining the behavior of the cut integrand as the unconstrained parameters of the cut loop momentum approach infinity. In this way we can produce compact forms for scalar integral coefficients. Applications of this method are presented for both QCD and electroweak processes, including an alternative form for the recently computed threemass triangle coefficient in the sixphoton amplitude A{sub 6}(1{sup }, 2{sup +}, 3{sup }, 4{sup +}, 5{sup }, 6{sup +}). The direct nature of this extraction procedure allows for a very straightforward automation of the procedure.},
doi = {10.1103/PhysRevD.75.125019},
journal = {Physical Review D},
number = ,
volume = ,
place = {United States},
year = {Mon Apr 16 00:00:00 EDT 2007},
month = {Mon Apr 16 00:00:00 EDT 2007}
}

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