Public Likelihood Combination

• Applicant: Dr. Carsten Burgard
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 551818918

Since the discovery of the Higgs boson, the focus in High Energy Physics has continuously shifted from a discovery-approach towards precision measurements. Crucially, highest precision can be achieved by combining information from different sources, including accelerator-based as well as astrophysical experiments. One of the most promising avenues for interpreting combined data in the last years has been the interpretation as part of a Standard Model Effective Field Theory (EFT). Combined measurements of Wilson coefficients rely on establishing inter-experiment collaborations in order to have access to the full internal representations of the statistical models. Within the context of a recent push towards open data policies, now and for the first time, a likelihood-level combination of results from large collaborations becomes feasible, provided the models can be converted into a common framework for statistical analysis. The emerging HEP Statistics Serialization Standard provides such a framework. Within this research proposal, state-of-the-art statistical software and data formats are leveraged to achieve an independent, likelihood-level combined EFT interpretation, using published likelihoods from large experiments. If funded, this research will serve to validate the usefulness of these published models, establish a procedure and software suite to use them for independent researchers, promote the adoption of the emerging standardization of likelihood models in HEP, and derive precise measurements of a large array of Wilson coefficients.

• DFG Programme: Research Grants
• International Connection: Switzerland, USA
• Cooperation Partners: Dr. Jonas Eschle; Dr. Lorenzo Moneta; Dr. Jonas Rembser