{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,8]],"date-time":"2025-11-08T17:57:32Z","timestamp":1762624652321,"version":"build-2065373602"},"reference-count":56,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,6,24]],"date-time":"2021-06-24T00:00:00Z","timestamp":1624492800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000921","name":"European Cooperation in Science and Technology","doi-asserted-by":"publisher","award":["CA16201"],"award-info":[{"award-number":["CA16201"]}],"id":[{"id":"10.13039\/501100000921","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004329","name":"Javna Agencija za Raziskovalno Dejavnost RS","doi-asserted-by":"publisher","award":["P1-0035"],"award-info":[{"award-number":["P1-0035"]}],"id":[{"id":"10.13039\/501100004329","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>We summarize our recent proposals for probing the CP-odd i\u03ba\u02dct\u00af\u03b35th interaction at the LHC and its projected upgrades directly using associated on-shell Higgs boson and top quark or top quark pair production. We first recount how to construct a CP-odd observable based on top quark polarization in Wb\u2192th scattering with optimal linear sensitivity to \u03ba\u02dc. For the corresponding hadronic process pp\u2192thj we then present a method of extracting the phase-space dependent weight function that allows to retain close to optimal sensitivity to \u03ba\u02dc. For the case of top quark pair production in association with the Higgs boson, pp\u2192tt\u00afh, with semileptonically decaying tops, we instead show how one can construct manifestly CP-odd observables that rely solely on measuring the momenta of the Higgs boson and the leptons and b-jets from the decaying tops without having to distinguish the charge of the b-jets. Finally, we introduce machine learning (ML) and non-ML techniques to study the phase-space optimization of such CP-odd observables. We emphasize a simple optimized linear combination \u03b1\u00b7\u03c9 that gives similar sensitivity as the studied fully fledged ML models. Using \u03b1\u00b7\u03c9 we review sensitivity projections to \u03ba\u02dc at HL-LHC, HE-LHC, and FCC-hh.<\/jats:p>","DOI":"10.3390\/sym13071129","type":"journal-article","created":{"date-parts":[[2021,6,24]],"date-time":"2021-06-24T23:22:14Z","timestamp":1624576934000},"page":"1129","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Optimized Probes of the CP Nature of the Top Quark Yukawa Coupling at Hadron Colliders"],"prefix":"10.3390","volume":"13","author":[{"given":"Darius A.","family":"Faroughy","sequence":"first","affiliation":[{"name":"Physik-Institut, Universitat Zurich, CH-8057 Zurich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bla\u017e","family":"Bortolato","sequence":"additional","affiliation":[{"name":"Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5183-8637","authenticated-orcid":false,"given":"Jernej F.","family":"Kamenik","sequence":"additional","affiliation":[{"name":"Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia"},{"name":"Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nejc","family":"Ko\u0161nik","sequence":"additional","affiliation":[{"name":"Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia"},{"name":"Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0798-9512","authenticated-orcid":false,"given":"Aleks","family":"Smolkovi\u010d","sequence":"additional","affiliation":[{"name":"Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,24]]},"reference":[{"key":"ref_1","first-page":"215","article-title":"A Minimal set of top-Higgs anomalous couplings","volume":"B821","year":"2009","journal-title":"Nucl. 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