Higgs couplings; multi-loop calculations; perturbative precision calculations; Higgs physics; supersymmetry
Baglio J., Campanario F., Glaus S., Mühlleitner M., Ronca J., Spira M. (2021), gg→HH : Combined uncertainties, in Physical Review D
, 103(5), 056002-056002.
Baglio Julien, Campanario Francisco, Glaus Seraina, Mühlleitner Margarete, Ronca Jonathan, Spira Michael, Streicher Juraj (2020), Higgs-pair production via gluon fusion at hadron colliders: NLO QCD corrections, in Journal of High Energy Physics
, 2020(4), 181-181.
Baglio J., Campanario F., Glaus S., Mühlleitner M., Spira M., Streicher J. (2019), Gluon fusion into Higgs pairs at NLO QCD and the top mass scheme, in The European Physical Journal C
, 79(6), 459-459.
The analysis of the Higgs boson properties is one of the most important endeavours at the LHC after the discovery of a Higgs-like scalar state in 2012 which shows increasing agreement with the properties of the Standard Model (SM) Higgs particle. The Higgs boson couplings to electroweak gauge bosons (W, Z, gg, gamma gamma) and fermions (tau lepton, bottom quark) have been tested and found to be in agreement with the SM predictions within errors. An important task for the future is the determination of the detailed nature of the Higgs boson coupling to gluons that constitutes the dominant Higgs boson production process via gluon fusion. The gluonic Higgs boson coupling is mediated by top and to a lesser extent bottom quark loops within the SM, However, it is highly relevant to test experimentally that this coupling is in agreement with the SM prediction or not. As an alternative to the SM this project will consider the minimal supersymmetric extension involving three neutral Higgs particles, two scalar ones h,H and a pseudoscalar Higgs particle. The extended Higgs sector will modify the couplings of the SM-like Higgs boson that is most likely the light scalar Higgs boson h and thus parametrizes deviations from the SM prediction. For a reliable analysis the experimental accuracies have to be matched by the uncertainties of the theoretical calculations of the production and decay processes involved. The topic of this work is the determination of the NLO SUSY-QCD corrections including the full quark, squark and gluino mass dependence to MSSM Higgs boson production via the loop-induced gluon fusion, gg -> A, which is the dominant pseudoscalar Higgs boson production process at the LHC in large regions of the MSSM parameter space. The goal of the project is a significant reduction of the theoretical uncertainties to a reliable level that is required for sophisticated experimental analyses and measurements at the LHC. In addition the novel corrections will have a significant impact on the size of the production cross sections.As a second ingredient this proposal includes the finalization of the full NLO QCD corrections to SM Higgs pair production via gluon fusion gg -> HH that constitutes the first process with a direct access to the trilinear Higgs self-coupling and thus a first experimental step towards a measurement of the Higgs potential. The results will reduce the residual theoretical uncertainties of the production cross section and the main distributions of experimental relevance.