The top-quark Yukawa coupling is extracted from the distribution of the top-quark pair (tt¯) invariant mass in proton-proton collisions using 140 fb−1 of data at s=13 TeV collected in 2015–2018 by the ATLAS experiment at the Large Hadron Collider. In the region near the production threshold, the tt¯ invariant mass spectrum is sensitive to electroweak virtual corrections, including contributions from Higgs boson exchange, thereby providing sensitivity to the top-quark Yukawa coupling. This is the first measurement in ATLAS that aims to obtain this coupling exploiting this approach. The tt¯ system is reconstructed in the single-lepton final state, requiring exactly one isolated electron or muon and at least four jets with at least two identified as originating from b-quarks. The measured Yukawa coupling is found to be in good agreement with the Standard Model prediction. An upper limit on the top-quark Yukawa coupling strength of Yt< 2.1 relative to the Standard Model prediction is observed at 95% confidence level, consistent with the expected sensitivity.

Measurement of the top-quark Yukawa coupling from tt¯ production in the lepton+jets final state using pp collisions at s=13 TeV with the ATLAS detector

Cobal M.;Giordani M. P.;Giugliarelli G.;Monzani S.;Panizzo G.;
2026-01-01

Abstract

The top-quark Yukawa coupling is extracted from the distribution of the top-quark pair (tt¯) invariant mass in proton-proton collisions using 140 fb−1 of data at s=13 TeV collected in 2015–2018 by the ATLAS experiment at the Large Hadron Collider. In the region near the production threshold, the tt¯ invariant mass spectrum is sensitive to electroweak virtual corrections, including contributions from Higgs boson exchange, thereby providing sensitivity to the top-quark Yukawa coupling. This is the first measurement in ATLAS that aims to obtain this coupling exploiting this approach. The tt¯ system is reconstructed in the single-lepton final state, requiring exactly one isolated electron or muon and at least four jets with at least two identified as originating from b-quarks. The measured Yukawa coupling is found to be in good agreement with the Standard Model prediction. An upper limit on the top-quark Yukawa coupling strength of Yt< 2.1 relative to the Standard Model prediction is observed at 95% confidence level, consistent with the expected sensitivity.
File in questo prodotto:
File Dimensione Formato  
JHEP01(2026)117.pdf

accesso aperto

Tipologia: Versione Editoriale (PDF)
Licenza: Creative commons
Dimensione 1.63 MB
Formato Adobe PDF
1.63 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11390/1328448
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 1
  • ???jsp.display-item.citation.isi??? 0
social impact