Release Note -- Vbfnlo-2.6.0
K. Arnold, J. Bellm, G. Bozzi, F. Campanario, C. Englert, B. Feigl, J. Frank, T. Figy, B. Jager, M. Kerner, M. Kubocz, C. Oleari, S. Palmer, M. Rauch, H. Rzehak, F. Schissler, O. Schlimpert, M. Spannowsky, D. Zeppenfeld
TL;DR
Vbfnlo-2.6.0 delivers extensive enhancements to multi-boson production at NLO QCD, including new same-sign W pair production via VBF, diboson processes with gluon-induced contributions, and triboson plus jet channels, along with anomalous couplings and a spin-2 resonance model for BSM studies. It also strengthens the numerical toolbox with expanded tensor-reduction routines, refined form-factor and parameterization schemes for HVV and triboson couplings, and improved histogram error handling and SUSY electroweak corrections. These updates enable more precise SM predictions and richer BSM scenarios in VBF, diboson, and triboson phenomenology, with practical impact on LHC analyses and beyond. The release maintains flexibility through configurable inputs (ANOM_CPL, MH_LOOPS, LOOPSQR_SWITCH) and provides new process IDs, enabling detailed comparisons between SM and anomalous/spin-2 scenarios while preserving unitarity via form factors such as $F = (1 + s/\Lambda^{2})^{-p}$.
Abstract
Vbfnlo is a flexible parton level Monte Carlo program for the simulation of vector boson fusion (VBF), double and triple vector boson (plus jet) production in hadronic collisions at next-to-leading order (NLO) in the strong coupling constant, as well as Higgs boson plus two jet production via gluon fusion at the one-loop level. This note briefly describes the main additional features and processes that have been added in the new release -- Vbfnlo Version 2.6.0. At NLO QCD diboson production (Wγ, WZ, ZZ, Zγand γγ), same-sign W pair production via vector boson fusion and the process Wγγj have been implemented (for which one-loop tensor integrals up to six-point functions are included). In addition, gluon induced diboson production can be studied separately at the leading order (one-loop) level. The diboson processes WW, WZ and Wγcan be run with anomalous gauge boson couplings, and anomalous couplings between a Higgs and a pair of gauge bosons is included in WW, ZZ, Zγand γγdiboson production. The code has also been extended to include anomalous gauge boson couplings for single vector boson production via VBF, and a spin-2 model has been implemented for diboson pair production via vector boson fusion.