Strength in numbers: Optimal and scalable combination of LHC new-physics searches

Araz, J. Y. , Buckley, A. , Fuks, B., Reyes-González, H., Waltenberger, W., Williamson, S. L. and Yellen, J. (2023) Strength in numbers: Optimal and scalable combination of LHC new-physics searches. SciPost Physics, 14(4), 077. (doi: 10.21468/scipostphys.14.4.077)

Abstract

To gain a comprehensive view of what the LHC tells us about physics beyond the Standard Model (BSM), it is crucial that different BSM-sensitive analyses can be combined. But in general search-analyses are not statistically orthogonal, so performing comprehensive combinations requires knowledge of the extent to which the same events co-populate multiple analyses’ signal regions. We present a novel, stochastic method to determine this degree of overlap, and a graph algorithm to efficiently find the combination of signal regions with no mutual overlap that optimises expected upper limits on BSM-model cross-sections. The gain in exclusion power relative to single-analysis limits is demonstrated with models with varying degrees of complexity, ranging from simplified models to a 19-dimensional supersymmetric model.

• Item Type: Articles
• Additional Information: AB and JY thank the Royal Society for studentship funding under URF Enhancement Grant RGF\EA\180252, and STFC for support under Consolidated Grant ST/S000887/1. The research of HRG is funded by the Italian PRIN grant 20172LNEEZ.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Buckley, Professor Andy and Araz, Mr Jack and Yellen, Jamie
• Authors: Araz, J. Y., Buckley, A., Fuks, B., Reyes-González, H., Waltenberger, W., Williamson, S. L., and Yellen, J.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: SciPost Physics
• Publisher: SciPost Foundation
• ISSN: 2542-4653
• ISSN (Online): 2542-4653
• Copyright Holders: Copyright © 2023 J. Y. Araz et al.
• First Published: First published in SciPost Phys. 14, 077 (2023)
• Publisher Policy: Reproduced under a Creative Commons licence

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
301827		Exotic diboson resonances and new physics global fits at the LHC	Andrew Buckley	The Royal Society (ROYSOC)	RGF\EA\180252	P&S - Physics & Astronomy
302375		Particle Physics Experiment (PPE) Consolidated	Anthony Doyle	Science and Technology Facilities Council (STFC)	ST/S000887/1	P&S - Physics & Astronomy