TY  - JOUR
PB  - SciPost Foundation
DO  - 10.21468/SciPostPhys.19.6.165
TI  - One-loop amplitudes for $t\bar{t}j$ and $t\bar{t}\gamma$ productions at the LHC through $\mathcal{O}(\epsilon^2)$
PY  - 2025/12/24
UR  - https://scipost.org/SciPostPhys.19.6.165
JF  - SciPost Physics
JA  - SciPost Phys.
VL  - 19
IS  - 6
SP  - 165
A1  - Bera, Souvik
AU  - Brancaccio, Colomba
AU  - Canko, Dhimiter
AU  - Hartanto, Heribertus Bayu
AB  - We present analytic expressions for the one-loop QCD helicity amplitudes contributing to top-quark pair production in association with a photon or a jet at the Large Hadron Collider (LHC), evaluated through $\mathcal{O}(\epsilon^2)$ in the dimensional regularisation parameter, $\epsilon$. These amplitudes are required to construct the two-loop hard functions that enter the NNLO QCD computation. The helicity amplitudes are expressed as linear combinations of algebraically independent components of the $\epsilon$-expanded master integrals, with the corresponding rational coefficients written in terms of momentum-twistor variables. We derive differential equations for the pentagon functions, which enable efficient numerical evaluation via generalised power series expansion method.
ER  -

@Article{10.21468/SciPostPhys.19.6.165,
	title={{One-loop amplitudes for $t\bar{t}j$ and $t\bar{t}\gamma$ productions at the LHC through $\mathcal{O}(\epsilon^2)$}},
	author={Souvik Bera and Colomba Brancaccio and Dhimiter Canko and Heribertus Bayu Hartanto},
	journal={SciPost Phys.},
	volume={19},
	pages={165},
	year={2025},
	publisher={SciPost},
	doi={10.21468/SciPostPhys.19.6.165},
	url={https://scipost.org/10.21468/SciPostPhys.19.6.165},
}