Journal of High Energy Physics

, 2019:172 | Cite as

Four-loop quark form factor with quartic fundamental colour factor

  • Roman N. Lee
  • Alexander V. Smirnov
  • Vladimir A. Smirnov
  • Matthias SteinhauserEmail author
Open Access
Regular Article - Theoretical Physics


We analytically compute the four-loop QCD corrections for the colour structure (d F abcd )2 to the massless non-singlet quark form factor. The computation involves non-trivial non-planar integral families which have master integrals in the top sector. We compute the master integrals by introducing a second mass scale and solving differential equations with respect to the ratio of the two scales. We present details of our calculational procedure. Analytical results for the cusp and collinear anomalous dimensions, and the finite part of the form factor are presented. We also provide analytic results for all master integrals expanded up to weight eight.


NLO Computations QCD Phenomenology 


Open Access

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Copyright information

© The Author(s) 2019

Authors and Affiliations

  • Roman N. Lee
    • 1
  • Alexander V. Smirnov
    • 2
  • Vladimir A. Smirnov
    • 3
    • 4
  • Matthias Steinhauser
    • 4
    Email author
  1. 1.Budker Institute of Nuclear PhysicsNovosibirskRussia
  2. 2.Research Computing CenterMoscow State UniversityMoscowRussia
  3. 3.Skobeltsyn Institute of Nuclear Physics of Moscow State UniversityMoscowRussia
  4. 4.Institut für Theoretische Teilchenphysik, Karlsruhe Institute of Technology (KIT)KarlsruheGermany

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