Ein Blick durch das Higgs-Fenster und darüber hinaus

01/04/2021 to 31/03/2024

While the Standard Model of particle physics describes results from collider experiments very well so far, there are still many questions the Standard Model cannot answer, such as what dark matter is or why there is more matter than antimatter in the universe. Therefore, extensions of the Standard Model that address these open questions are considered. Often, these extensions possess an extended Higgs sector, i.e. the discovered Higgs boson would be only one of several with possibly slightly different properties than the ones of the Higgs boson predicted by the Standard Model - hence, the properties of the discovered Higgs boson can serve as a window to new physics. However, accurate experimental measurements as well as precise theoretical predictions are required to open it. Due to the lacking experimental evidence for the one or the other SM extension, it is required to either study effective-field theories or, complementary, many different extensions of the Standard Model. In particular for the latter, the automation of calculations of precise predictions of observables is needed.

The aim of this project is two-fold: On the one hand, we will study the experimentally allowed values of
the Higgs-boson properties in the context of different extensions of the
Standard Model, improve their predictions and implement them into analysis
tools, identify viable scenarios to benchmark the experimental methods, and
search for novel strategies of how to measure the Higgs-boson properties. On the other hand, we will exploit the examples of these investigations to gain a conceptual understanding, which is needed and will be applied for the development of crucial tools for the automation of the calculations, which will be applicable beyond the Higgs-boson studies. We will address different specific extensions of the Standard Model explicitly and also consider the linking of a specific model to an effective-field theory description.