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arXiv · 2605.24441

On the Statistical Interpretation of Discoveries in LHC Data

S. V. Chekanov·E. J. Weik
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Abstract

We examine discovery criteria at the Large Hadron Collider (LHC) within a model-independent framework, with particular emphasis on the statistical signatures of new physics. This study is motivated by the recent shift from model-specific searches based on a small number of distributions to broad, model-agnostic strategies, which offer substantially greater sensitivity to unexpected phenomena. We revisit the well-known criterion of a local statistical significance of $5\,\sigma$ for the observation of new phenomena in invariant-mass distributions and discuss how this threshold should be modified to account for look-elsewhere effects arising not only from multiple bins within a given distribution, but also from the simultaneous consideration of multiple distributions. We present a simple but statistically conservative relation between local and global significances in the presence of multiple invariant-mass distributions at the LHC, which can serve as a useful first approximation for planning future measurements.

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S. V. Chekanov, E. J. Weik. 2026-05-23. On the Statistical Interpretation of Discoveries in LHC Data. https://doi.org/10.1088/1361-6471%2Fae996d

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