Hard Matching for Boosted Tops at Two Loops

André H. Hoang, Aditya Pathak, Piotr Pietrulewicz, Iain W. Stewart

Publications: Contribution to journalArticlePeer Reviewed

Abstract

Abstract: Cross sections for top quarks provide very interesting physics opportunities, being both sensitive to new physics and also perturbatively tractable due to the large top quark mass. Rigorous factorization theorems for top cross sections can be derived in several kinematic scenarios, including the boosted regime in the peak region that we consider here. In the context of the corresponding factorization theorem for e +e collisions we extract the last missing ingredient that is needed to evaluate the cross section differential in the jet-mass at two-loop order, namely the matching coefficient at the scale μ≃m t. Our extraction also yields the final ingredients needed to carry out logarithmic re-summation at next-to-next-to-leading logarithmic order (or N 3LL if we ignore the missing 4-loop cusp anomalous dimension). This coefficient exhibits an amplitude level rapidity logarithm starting at (Formula presented.) due to virtual top quark loops, which we treat using rapidity renormalization group (RG) evolution. Interestingly, this rapidity RG evolution appears in the matching coefficient between two effective theories around the heavy quark mass scale μ ≃ m t.

Original languageEnglish
Article number59
Number of pages36
JournalJournal of High Energy Physics
Volume2015
Issue number12
DOIs
Publication statusPublished - Dec 2015

Austrian Fields of Science 2012

  • 103012 High energy physics

Keywords

  • QCD Phenomenology
  • NLO Computations
  • HIGGS-BOSON MASSES
  • HEAVY
  • QUARK
  • SOFT

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