Publications

Order by: publication date number of citations

• Two-loop gauge coupling $β$-function in a four-dimensional framework: the Standard Model case

  Adriano Cherchiglia

  SciPost Phys. Proc. 7, 043 (2022) · published 22 June 2022 | Toggle abstract · pdf

  At present, the gauge coupling $\beta$-function in the Standard Model (SM) is known up to four-loop order. As most SM calculations, dimensional regularization was employed. Despite its striking success, other regularization schemes have emerged, which aim to stay in the physical dimension as far as possible. In this contribution, we apply Implicit Regularization, a scheme defined in momentum space that complies with BPHZ, to obtain the two-loop gauge coupling $\beta$-function in the Standard Model. We reproduce the same result obtained when applying dimensional regularization.

  3 citations

• NNLO photon fragmentation within antenna subtraction

  Thomas Gehrmann, Robin Schürmann

  SciPost Phys. Proc. 7, 042 (2022) · published 22 June 2022 | Toggle abstract · pdf

  We report on our recent progress towards including the photon fragmentation contribution in next-to-next-to-leading order (NNLO) QCD predictions for photon production cross sections. This extension to previous NNLO calculations requires the identification of the photon in singular parton-photon collinear limits. We discuss how these limits can be subtracted within antenna subtraction using fragmentation antenna functions and we outline their integration.

  1 citation

• A semi-numerical method for one-scale problems applied to the $\overline{\rm MS}$-on-shell relation

  Matteo Fael, Fabian Lange, Kay Schönwald, Matthias Steinhauser

  SciPost Phys. Proc. 7, 041 (2022) · published 22 June 2022 | Toggle abstract · pdf

  We discuss a practical approach to compute master integrals entering physical quantities which depend on one parameter. As an example we consider four-loop QCD corrections to the relation between a heavy quark mass defined in the $\overline{\rm MS}$ and on-shell scheme in the presence of a second heavy quark.

  2 citations

• Next-to-leading power SCET in Higgs amplitudes induced by light quarks

  Xing Wang

  SciPost Phys. Proc. 7, 040 (2022) · published 22 June 2022 | Toggle abstract · pdf

  In this article, we report how to use the "plus-type" subtraction scheme to deal with endpoint divergences in $h\rightarrow\gamma\gamma$ or $gg\rightarrow h$ amplitudes induced by light quark loop, which can be formulated by next-to-leading power (NLP) SCET. This subtraction is ensured by two re-factorization conditions, which have been proven to all orders in $\alpha_s$. Based on these conditions, cutoffs emerge naturally after some re-arrangements to handle endpoint divergences and renormalization is compatible with that. Our formalism can analytically reproduce three-loop amplitudes up to $\ln^3(-M_h^2/m_b^2-i0)$ and resum to next-to-leading logarithm and beyond.

  1 citation

• The two-loop radiative gluon jet function for $gg\to h$ via a light quark loop

  Marvin Schnubel

  SciPost Phys. Proc. 7, 039 (2022) · published 22 June 2022 | Toggle abstract · pdf

  The Higgs-boson production channel $gg\to h$ mediated by light-quark loops receives large logarithmic corrections in QCD, which can be resummed using factorization formulae derived in soft-collinear effective theory. In these factorization formulae the radiative gluon jet function appears, which is a central object in the study of factorization beyond the leading order in scale ratios. We calculate this function at two-loop order for the first time and present the subtleties that come along with this.

• PMC$_\infty$: Infinite-Order Scale-Setting method using the Principle of Maximum Conformality and preserving the Intrinsic Conformality

  Leonardo Di Giustino, Stanley J. Brodsky, Xing-Gang Wu, Sheng-Quan Wang

  SciPost Phys. Proc. 7, 038 (2022) · published 21 June 2022 | Toggle abstract · pdf

  We show results for Thrust and C-parameter in $e^+ e^-$ annihilation to 3 jets obtained using the recently developed new method for eliminating the scale ambiguity and the scheme dependence in pQCD namely the Infinite-Order Scale-Setting method using the Principle of Maximum Conformality (PMC$_\infty$). This method preserves an important underlying property of gauge theories: intrinsic Conformality (iCF). It leads to a remarkably efficient method to eliminate the conventional renormalization scale ambiguity at any order in pQCD. A comparison with Conventional Scale Setting method (CSS) is also shown.

• Recent progress on two-loop massless pentabox integrals with one off-shell leg

  D. Canko, A. Kardos, C. G. Papadopoulos, A. V Smirnov, N. Syrrakos, C. Wever

  SciPost Phys. Proc. 7, 037 (2022) · published 21 June 2022 | Toggle abstract · pdf

  Analytic expressions in terms of polylogarithmic functions for all three families of planar two-loop five-point Master Integrals with one off-shell leg are presented. The Simplified Differential Equations approach is the only known way to fulfil this task due to its unique factorisation property of the symbols of the canonical differential equation. The results are relevant to the study of many $2\to 3$ scattering processes of interest at the LHC.

• Two-Loop renormalization of High-Dimensional QCD operators and Higgs EFT amplitudes

  Qingjun Jin, Ke Ren, Gang Yang, Rui Yu

  SciPost Phys. Proc. 7, 036 (2022) · published 21 June 2022 | Toggle abstract · pdf

  We consider two-loop renormalization of high-dimensional operators in QCD and the relevant Higgs EFT amplitudes. Efficient unitarity-IBP strategy is used to compute the two-loop minimal form factors of length-3 operators up to dimension sixteen. From the ultraviolet divergences of form factor results, we extract the renormalization matrices and compute anomalous dimensions. We also obtain the analytic finite remainder functions which exhibit several universal transcendentality structures. The form factors we compute are equivalent to Higgs plus three-gluon amplitudes that capture high-order top mass corrections in Higgs effective field theory.

• W+c-jet production at the LHC with NNLO QCD accuracy

  Michal Czakon, Alexander Mitov, Mathieu Pellen, Rene Poncelet

  SciPost Phys. Proc. 7, 035 (2022) · published 21 June 2022 | Toggle abstract · pdf

  In these proceedings, we highlight some aspects of the recent computation of NNLO QCD corrections for W production in association with a charm jet at the LHC. The results are presented in the form of cross sections and differential distributions and are compared to ATLAS data.

• NLO electroweak and QCD corrections to off-shell ttW production at the LHC

  Ansgar Denner, Giovanni Pelliccioli

  SciPost Phys. Proc. 7, 034 (2022) · published 21 June 2022 | Toggle abstract · pdf

  The foreseen luminosities for the next LHC runs will enable precise differential measurements of the associated production of top-antitop pairs with a W boson. Therefore, providing accurate theory predictions for this process is needed for realistic final states. We present the first combination of NLO electroweak and QCD corrections to off-shell ttW$^+$ production in the three-charged-lepton channel, including non-resonant effects, full spin-correlations and interferences. Such radiative corrections comprise the electroweak and QCD corrections to the leading QCD order, and the QCD corrections to the leading electroweak order.

  1 citation