Loops and Legs in Quantum Field Theory

Session

Parallel B

15 Apr 2024, 14:30

Philipp Melanchthon

Conveners

Parallel B

• Massimiliano Grazzini (University of Zurich)

Parallel B

• Massimiliano Grazzini (University of Zurich)

3. Analytic electroweak corrections to gg -> HH

Hantian Zhang (Karlsruhe Institute of Technology)

15/04/2024, 14:30

LHC

We consider next-to-leading order electroweak corrections to Higgs boson pair production. This requires the computation of two-loop four-point amplitudes with massive internal particles such as top quarks, Higgs and gauge bosons. We perform analytic calculations in various kinematical limits and show that their combination covers the whole phase space, thus circumventing time-consuming...

45. Higgs pair production at NNLO

Joshua Davies (University of Liverpool)

15/04/2024, 15:00

LHC

The two-loop (NLO) corrections to Higgs pair production are large, and suffer from large uncertainties due to the renormalization scheme and scale of the top quark mass. This strongly motivates a three-loop (NNLO) computation of the cross section. In this talk I will discuss progress towards this goal, by investigating the NNLO virtual corrections in an expansion around the forward scattering...

93. Higgs Self-Coupling and Yukawa Corrections to Higgs Boson Pair Production

Matthias Kerner (KIT)

15/04/2024, 15:30

LHC

We present a calculation of the electroweak corrections to Higgs boson pair production in gluon fusion, involving Yukawa interactions and Higgs self-couplings only. The integrals appearing in the two-loop amplitude are evaluated numerically using both sector decomposition and series expansion of the differential equations. The full dependence on the masses of the top quark and Higgs boson are...

68. Status of two-loop QCD corrections to pp->ttj scattering

Matteo Becchetti (University of Bologna)

15/04/2024, 16:30

LHC

I will discuss recent developments in the computation of the two-loop QCD corrections to top pair production in association with a jet in the leading colour approximation. In particular, I will focus on the usage of differential equations and generalised series expansions in the evaluation of master integrals, and I will describe some aspects of the analytic structure of the solution.

38. Complete NLO corrections to top-quark pair production with isolated photons

Malgorzata WOREK (RWTH Aachen University)

15/04/2024, 17:00

LHC

We report on the computation of NLO QCD corrections to top-quark pair production in association with two photons at the LHC. Higher-order effects and photon bremsstrahlung are taken into account in the production and decays of the top-quark pair. Top-quark and W-boson decays are treated in the Narrow Width Approximation conserving spin correlations up to NLO in QCD. This is the first time that...

65. Towards a full NNLO QCD calculation of $\Delta \Gamma$ in the $B$-$\overline{B}$ system

Pascal Reeck (KIT TTP)

15/04/2024, 17:30

In this talk I will discuss recent advances made in the calculation of the NNLO QCD corrections to the width difference between B and B mesons. This work focuses on the perturbative high-energy part of the calculation, more specifically the matching coefficients between the Δ B = 1 effective operators of the Weak Interaction and the Δ B = 2 transition operator are calculated as a deep...

101. 2-loop Quarkonium Hamiltonian (Non-annihilation Channel)

Yukinari Sumino (Tohoku University)

15/04/2024, 18:00

We calculate the Hamiltonian of a heavy quarkonium system at two loops of
potential-NRQCD effective field theory (Non-annihilation channel).
We compute the quark-antiquark scattering amplitude in the non-annihilation
channel up to two loops in QCD, in the non-relativistic region in expansion in
beta. Then we match it to the scattering amplitude in potential-NRQCD.
We develop a method by...