Infrared and transcendental structure of twoloop supersymmetric QCD amplitudes
Abstract
Using a careful choice of infrared (IR) subtraction scheme, we demonstrate cancellation of all terms with transcendental weights 0, 1, 2 from the finite part of the fullcolor twoloop fourgluon N = 2 supersymmetric QCD amplitude, with Nf massless supersymmetric quarks. This generalizes the previously observed cancellation of weight2 terms in the superconformal theory, where N_{f} = 2N_{c} for gauge group SU(N_{c}). The subtraction scheme follows naturally both from general IR factorization principles and from an integrandlevel analysis of divergences in this amplitude. The divergences are written in terms of scalar triangle integrals whose expressions are known to all orders in the dimensional regulator ϵ = (4  D)/2. We also present integrated expressions for the fullcolor twoloop fourpoint amplitudes with both matter and vectors on external legs in which lowerweight terms also cancel using an appropriate IR scheme. This provides us with values for the twoloop cusp, gluonic, and quark anomalous dimensions in N = 2 supersymmetric QCD, which are crosschecked between the three different amplitudes.
 Authors:

 Uppsala Univ. (Sweden); SLAC National Accelerator Lab., Menlo Park, CA (United States)
 Uppsala Univ. (Sweden)
 ETH Zurich (Switzerland)
 Publication Date:
 Research Org.:
 SLAC National Accelerator Lab., Menlo Park, CA (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC)
 OSTI Identifier:
 1605201
 Report Number(s):
 SLACPUB17488
Journal ID: ISSN 10298479
 Grant/Contract Number:
 AC0276SF00515
 Resource Type:
 Accepted Manuscript
 Journal Name:
 Journal of High Energy Physics (Online)
 Additional Journal Information:
 Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2020; Journal Issue: 1; Journal ID: ISSN 10298479
 Publisher:
 Springer Berlin
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
Citation Formats
Kälin, Gregor, Mogull, Gustav, Ochirov, Alexander, and Verbeek, Bram. Infrared and transcendental structure of twoloop supersymmetric QCD amplitudes. United States: N. p., 2020.
Web. doi:10.1007/jhep01(2020)068.
Kälin, Gregor, Mogull, Gustav, Ochirov, Alexander, & Verbeek, Bram. Infrared and transcendental structure of twoloop supersymmetric QCD amplitudes. United States. doi:https://doi.org/10.1007/jhep01(2020)068
Kälin, Gregor, Mogull, Gustav, Ochirov, Alexander, and Verbeek, Bram. Mon .
"Infrared and transcendental structure of twoloop supersymmetric QCD amplitudes". United States. doi:https://doi.org/10.1007/jhep01(2020)068. https://www.osti.gov/servlets/purl/1605201.
@article{osti_1605201,
title = {Infrared and transcendental structure of twoloop supersymmetric QCD amplitudes},
author = {Kälin, Gregor and Mogull, Gustav and Ochirov, Alexander and Verbeek, Bram},
abstractNote = {Using a careful choice of infrared (IR) subtraction scheme, we demonstrate cancellation of all terms with transcendental weights 0, 1, 2 from the finite part of the fullcolor twoloop fourgluon N = 2 supersymmetric QCD amplitude, with Nf massless supersymmetric quarks. This generalizes the previously observed cancellation of weight2 terms in the superconformal theory, where Nf = 2Nc for gauge group SU(Nc). The subtraction scheme follows naturally both from general IR factorization principles and from an integrandlevel analysis of divergences in this amplitude. The divergences are written in terms of scalar triangle integrals whose expressions are known to all orders in the dimensional regulator ϵ = (4  D)/2. We also present integrated expressions for the fullcolor twoloop fourpoint amplitudes with both matter and vectors on external legs in which lowerweight terms also cancel using an appropriate IR scheme. This provides us with values for the twoloop cusp, gluonic, and quark anomalous dimensions in N = 2 supersymmetric QCD, which are crosschecked between the three different amplitudes.},
doi = {10.1007/jhep01(2020)068},
journal = {Journal of High Energy Physics (Online)},
number = 1,
volume = 2020,
place = {United States},
year = {2020},
month = {1}
}
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