Theoretical Particle Physics

LHC and flavour physics phenomenology

We work on the interface between theoretical predictions and experimental measurements at the Large Hadron Collider (LHC) and dedicated flavour facilities, combining precision Standard Model calculations with searches for physics beyond it.

Flavour physics

Flavour-changing processes in beauty and charm hadrons are among the most sensitive probes of physics beyond the Standard Model: heavy new particles can contribute virtually to rare and CP-violating decays even when they lie far beyond the direct reach of the LHC. The LHCb experiment, together with Belle II and the general-purpose LHC detectors, is producing an increasingly precise picture of these processes.

We develop theoretical tools, including QCD factorisation, light-cone sum rules and matching to lattice QCD results, together with global analyses within the Standard Model effective field theory, to interpret these measurements, control hadronic uncertainties and translate experimental results into robust constraints on new physics.

Jet physics

Jets are the dominant final-state objects at hadron colliders and are fundamental to a vast range of measurements, from precision determinations of Standard Model parameters to searches for new phenomena. Predicting jet observables to the accuracy demanded by modern LHC data requires controlling QCD radiation across widely separated scales, where fixed-order perturbation theory alone is insufficient and large logarithms must be resummed to all orders.

We develop and apply resummation techniques, study the structure of infrared singularities, and work on event-shape and jet-substructure observables that sharpen tests of QCD and improve sensitivity to new physics.

LHC precision phenomenology

Extracting new physics from LHC data, or pinning down Standard Model parameters with percent-level accuracy, demands theoretical predictions of matching precision. This requires higher-order perturbative calculations in QCD and the electroweak theory, together with their consistent combination and matching to parton showers.

We work on multi-loop and multi-leg amplitudes, NLO and NNLO predictions for collider processes, and the automation of precision calculations through dedicated simulation frameworks. These developments feed directly into the interpretation of LHC measurements, supporting both Standard Model tests and the search for deviations that might signal new physics.

BSM phenomenology

A common motivation across our work is the search for physics beyond the Standard Model. Direct searches at the LHC and indirect probes from rare decays and precision measurements are highly complementary, and a coherent assessment of any BSM scenario requires combining both. We use the Standard Model effective field theory as a model-independent framework for global analyses and also study specific extensions, such as extended Higgs sectors or models addressing the flavour and hierarchy problems, guiding experimental analyses and interpreting the available constraints.

Related members

Andrea Banfi, Sebastian Jaeger, Jonas Lindert