https://doi.org/10.1140/epjc/s10052-023-12097-3
Regular Article - Theoretical Physics
On the two-loop BSM corrections to 
in the aligned THDM
1
Dipartimento di Matematica e Fisica, Università di Roma Tre, Roma Tre, and INFN, Sezione di Roma Tre, I-00146, Rome, Italy
2
CNRS, Laboratoire de Physique Théorique et Hautes Energies, LPTHE, Sorbonne Université, 75005, Paris, France
Received:
18
July
2023
Accepted:
1
October
2023
Published online:
18
October
2023
We compute the two-loop BSM contributions to the decay width in the aligned THDM. We adopt the simplifying assumptions of vanishing EW gauge couplings and vanishing mass of the SM-like Higgs boson, which allow us to exploit a low-energy theorem connecting the 
amplitude to the derivative of the photon self-energy w.r.t. the Higgs field. We briefly discuss the numerical impact of the newly-computed contributions, showing that they may be required for a precise determination of 
in scenarios where the quartic Higgs couplings are large.
© The Author(s) 2023
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