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arXiv · 2611.05463

Top Spin and CP from Equivariant Transformers

Henning Bahl·Marco Menen·Antoine Petitjean·Tilman Plehn
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Abstract

Measurements of spin correlations and CP are an exciting and challenging part of the precision-LHC program. We first show how L-GATr-slim, as a Lorentz-equivariant transformer, significantly boosts the spin analyzing power for hadronic top quarks. We then show how adding a pseudoscalar channel to its architecture allows us to learn and interpret optimal observables and their CP properties. We demonstrate this for WBF-Higgs production at parton level and top pair production including detector effects.

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Henning Bahl, Marco Menen, Antoine Petitjean, Tilman Plehn. 2026-11-03. Top Spin and CP from Equivariant Transformers. https://arxiv.org/abs/2611.05463

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