TY  - JOUR
A1  - Denner, Ansgar
A1  - Jenniches, Laura
A1  - Lang, Jean-Nicolas
A1  - Sturm, Christian
T1  - Gauge-independent (MS)over-bar renormalization in the 2HDM
JF  - Journal of High Energy Physics
N2  - We present a consistent renormalization scheme for the CP-conserving Two-Higgs-Doublet Model based on (MS)over-bar renormalization of the mixing angles and the soft-Z 2-symmetry-breaking scale M sb in the Higgs sector. This scheme requires to treat tadpoles fully consistently in all steps of the calculation in order to provide gauge-independent S-matrix elements. We show how bare physical parameters have to be defined and verify the gauge independence of physical quantities by explicit calculations in a general R ξ -gauge. The procedure is straightforward and applicable to other models with extended Higgs sectors. In contrast to the proposed scheme, the (MS)over-bar renormalization of the mixing angles combined with popular on-shell renormalization schemes gives rise to gauge-dependent results already at the one-loop level. We present explicit results for electroweak NLO corrections to selected processes in the appropriately renormalized Two-Higgs-Doublet Model and in particular discuss their scale dependence.
KW  - NLO Computations
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166402
VL  - 09
IS  - 115
ER  - 
TY  - JOUR
A1  - Denner, Ansgar
A1  - Lang, Jean-Nicolas
A1  - Pellen, Mathieu
A1  - Uccirati, Sandro
T1  - Higgs production in association with off-shell top-antitop pairs at NLO EW and QCD at the LHC
JF  - Journal of High Energy Physics
N2  - We present NLO electroweak corrections to Higgs production in association with off-shell top-antitop quark pairs. The full process pp → e +νeµ −ν¯µbb¯H is considered, and hence all interference, off-shell, and non-resonant contributions are taken into account.
The electroweak corrections turn out to be below one per cent for the integrated cross section but can exceed 10% in certain phase-space regions. In addition to its phenomenological relevance, the computation constitutes a major technical achievement as the full NLO virtual corrections involving up to 9-point functions have been computed exactly. The results of the full computation are supported by two calculations in the double-pole approximation. These also allow to infer the effect of off-shell contributions and emphasise their importance especially for the run II of the LHC. Finally, we present combined predictions featuring both NLO electroweak and QCD corrections in a common set-up that will help the experimental collaborations in their quest of precisely measuring the aforementioned process.
KW  - high energy physics
KW  - NLO computations
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-171871
IS  - 2
ER  - 
TY  - JOUR
A1  - Denner, Ansgar
A1  - Lang, Jean-Nicolas
A1  - Uccirati, Sandro
T1  - NLO electroweak corrections in extended Higgs sectors with RECOLA2
JF  - Journal of High Energy Physics
N2  - We present the computer code RECOLA2 along with the first NLO electroweak corrections to Higgs production in vector-boson fusion and updated results for Higgs strahlung in the Two-Higgs-Doublet Model and Higgs-Singlet extension of the Standard Model. A fully automated procedure for the generation of tree-level and one-loop matrix elements in general models, including renormalization, is presented. We discuss the application of the Background-Field Method to the extended models. Numerical results for NLO electroweak cross sections are presented for different renormalization schemes in the Two-Higgs-Doublet Model and the Higgs-Singlet extension of the Standard Model. Finally, we present distributions for the production of a heavy Higgs boson.
KW  - NLO computations
KW  - phenomenological models
KW  - Higgs boson
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170673
VL  - 7
IS  - 87
ER  -