Optimized probes of CP-odd effects in the tt¯h process at hadron colliders

• Published in: Nuclear physics. B Vol. 964; p. 115328
• Main Authors: Bortolato, Blaž, F. Kamenik, Jernej, Košnik, Nejc, Smolkovič, Aleks
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2021; Elsevier
• ISSN: 0550-3213; 1873-1562
• DOI: 10.1016/j.nuclphysb.2021.115328

We use machine learning (ML) and non-ML techniques to study optimized CP-odd observables, directly and maximally sensitive to the CP-odd iκ˜t¯γ5th interaction at the LHC and prospective future hadron colliders using the final state with a Higgs boson and a top quark pair, pp→tt¯h, followed by semileptonic t decays. We perform phase-space optimization of manifestly CP-odd observables (ω), sensitive to the sign of κ˜, and constructed from experimentally accessible final state momenta. We identify a simple optimized linear combination α⋅ω that gives similar sensitivity as the studied fully fledged ML models. Using α⋅ω we project the expected sensitivities to κ˜ at HL-LHC, HE-LHC, and FCC-hh.