Infrared and transcendental structure of two-loop supersymmetric QCD amplitudes

doi:10.1007/jhep01(2020)068

This content will become publicly available on January 1, 2021

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:

Kälin, Gregor;

; Ochirov, Alexander; Verbeek, Bram

Publication Date:: 2020-01-01

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

Country of Publication:: United States

Language:: English

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.

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                    Kälin, Gregor, Mogull, Gustav, Ochirov, Alexander, & Verbeek, Bram. Infrared and transcendental structure of two-loop supersymmetric QCD amplitudes.  United States.  doi:10.1007/jhep01(2020)068.

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                    Kälin, Gregor, Mogull, Gustav, Ochirov, Alexander, and Verbeek, Bram. Wed .  
        "Infrared and transcendental structure of two-loop supersymmetric QCD amplitudes".  United States.  doi:10.1007/jhep01(2020)068.

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@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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Works referenced in this record:

Multi-loop amplitudes and resummation
journal, January 2003

Sterman, George; Tejeda-Yeomans, Maria E.
Physics Letters B, Vol. 552, Issue 1-2
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Dunbar, David C.; Perkins, Warren B.
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conference, October 2018

Badger, Simon; Bronnum-Hansen, Christian; Gehrmann, Thomas
Proceedings of Loops and Legs in Quantum Field Theory — PoS(LL2018)
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Similar Records

This content will become publicly available on January 1, 2021

Title: Infrared and transcendental structure of two-loop supersymmetric QCD amplitudes

Abstract

Citation Formats

Multi-loop amplitudes and resummation journal, January 2003

Two-Loop Six Gluon All-Plus Helicity Amplitude journal, August 2016

Multiple polylogarithms, cyclotomy and modular complexes journal, January 1998

Supersymmetric dimensional regularization via dimensional reduction journal, June 1979

4D Conformal Field Theories and Strings on Orbifolds journal, June 1998

A theorem on analytical calculability of 4-loop renormalization group functions journal, March 1981

Applications of integrand reduction to two-loop five-point scattering amplitudes in QCD conference, October 2018

Multi-loop amplitudes and resummation
journal, January 2003

Two-Loop Six Gluon All-Plus Helicity Amplitude
journal, August 2016

Multiple polylogarithms, cyclotomy and modular complexes
journal, January 1998

Supersymmetric dimensional regularization via dimensional reduction
journal, June 1979

4D Conformal Field Theories and Strings on Orbifolds
journal, June 1998

A theorem on analytical calculability of 4-loop renormalization group functions
journal, March 1981

Applications of integrand reduction to two-loop five-point scattering amplitudes in QCD
conference, October 2018