Constructing model-agnostic likelihoods, a method for the reinterpretation of particle physics results

Gärtner, Lorenz; Hartmann, Nikolai; Heinrich, Lukas; Horstmann, Malin; Kuhr, Thomas; Reboud, Méril; Stefkova, Slavomira; van Dyk, Danny

Abstract

Experimental High Energy Physics has entered an era of precision measurements. However, measurements of many of the accessible processes assume that the final states’ underlying kinematic distribution is the same as the Standard Model prediction. This assumption introduces an implicit model-dependency into the measurement, rendering the reinterpretation of the experimental analysis complicated without reanalysing the underlying data. We present a novel reweighting method in order to perform reinterpretation of particle physics measurements. It makes use of reweighting the Standard Model templates according to kinematic signal distributions of alternative theoretical models, prior to performing the statistical analysis. The generality of this method allows us to perform statistical inference in the space of theoretical parameters, assuming different kinematic distributions, according to a beyond Standard Model prediction. We implement our method as an extension to the pyhf software and interface it with the EOS software, which allows us to perform flavor physics phenomenology studies. Furthermore, we argue that, beyond the pyhf or HistFactory likelihood specification, only minimal information is necessary to make a likelihood model-agnostic and hence easily reinterpretable. We showcase that publishing such likelihoods is crucial for a full exploitation of experimental results.

Citation

Gärtner, L., Hartmann, N., Heinrich, L., Horstmann, M., Kuhr, T., Reboud, M., Stefkova, S., & van Dyk, D. (2024). Constructing model-agnostic likelihoods, a method for the reinterpretation of particle physics results. The European Physical Journal C, 84(7), Article 693. https://doi.org/10.1140/epjc/s10052-024-13038-4

• Journal Article Type: Article
• Acceptance Date: Jun 22, 2024
• Online Publication Date: Jul 14, 2024
• Publication Date: Jul 14, 2024
• Deposit Date: Jul 24, 2024
• Publicly Available Date: Jul 24, 2024
• Journal: The European Physical Journal C
• Print ISSN: 1434-6044
• Electronic ISSN: 1434-6052
• Publisher: SpringerOpen
• Peer Reviewed: Peer Reviewed
• Volume: 84
• Issue: 7
• Article Number: 693
• DOI: https://doi.org/10.1140/epjc/s10052-024-13038-4
• Public URL: https://durham-repository.worktribe.com/output/2606121