Optimized probes of CP-odd effects in the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"> <mml:mi>t</mml:mi> <mml:mover accent="true"> <mml:mrow> <mml:mi>t</mml:mi> </mml:mrow> <mml:mrow> <mml:mo stretchy="false">¯</mml:mo> </mml:mrow> </mml:mover> <mml:mi>h</mml:mi> </mml:math> process at hadron colliders
Blaž Bortolato, Jernej F. Kamenik, Nejc Košnik, Aleks Smolkovič
Abstract
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.