Phenomenology Studies of LHC Physics and Strong Interactions

Close collaboration with theoretical physicists on phenomenological aspects, in particular with the strong theory groups in the Zurich area, has always been most fruitful. For example, the collaboration with Prof. Anastasiou (ETH Zurich) has led to papers on the impact of higher-order Quantum Chromodynamics (QCD) corrections (at the next-to-next-to-leading order, NNLO, level) on the Higgs search in the WW channel. Together with the group of Prof. Gehrmann (Univ. of Zurich), a first determination of the strong coupling constant from event-shape data at NNLO precision was achieved, as well as a similar first measurement based on the three-jet rate in e+e- annihilations, leading to one of the most precise values for this fundamental parameter. Regarding the work on the strong coupling constant, there has been a close collaboration with Prof. G. Salam (Oxford University) and S. Bethke (MPI Munich) in the context of the determination of the world average value (published in the Particle Data Group’s Review on Particle Physics), and its measurement using a combination of top-pair production cross section results from the Tevatron and the LHC.