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Title: Infrared and transcendental structure of two-loop 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 full-color two-loop four-gluon N = 2 supersymmetric QCD amplitude, with Nf massless supersymmetric quarks. This generalizes the previously observed cancellation of weight-2 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 integrand-level 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 full-color two-loop four-point amplitudes with both matter and vectors on external legs in which lower-weight terms also cancel using an appropriate IR scheme. This provides us with values for the two-loop cusp, gluonic, and quark anomalous dimensions in N = 2 supersymmetric QCD, which are cross-checked between the three different amplitudes.

Authors:
 [1]; ORCiD logo [2];  [3];  [2]
  1. Uppsala Univ. (Sweden); SLAC National Accelerator Lab., Menlo Park, CA (United States)
  2. Uppsala Univ. (Sweden)
  3. 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):
SLAC-PUB-17488
Journal ID: ISSN 1029-8479
Grant/Contract Number:  
AC02-76SF00515
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 1029-8479
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 two-loop 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 two-loop 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 two-loop 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 two-loop 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 full-color two-loop four-gluon N = 2 supersymmetric QCD amplitude, with Nf massless supersymmetric quarks. This generalizes the previously observed cancellation of weight-2 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 integrand-level 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 full-color two-loop four-point amplitudes with both matter and vectors on external legs in which lower-weight terms also cancel using an appropriate IR scheme. This provides us with values for the two-loop cusp, gluonic, and quark anomalous dimensions in N = 2 supersymmetric QCD, which are cross-checked 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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