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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - CP Properties of Higgs Boson Interactions with Top Quarks in the tt¯H and tH Processes Using H→γγ with the ATLAS Detector
T2 - Physical review letters
AU - Collaboration, ATLAS
AU - Barton, A.E.
AU - Bertram, I.A.
AU - Borissov, G.
AU - Bouhova-Thacker, E.V.
AU - Fox, H.
AU - Henderson, R.C.W.
AU - Jones, R.W.L.
AU - Kartvelishvili, V.
AU - Long, R.E.
AU - Love, P.A.
AU - Muenstermann, D.
AU - Parker, A.J.
AU - Sanderswood, Izaac
AU - Smizanska, M.
AU - Tee, A.S.
AU - Walder, J.
AU - Wharton, A.M.
AU - Whitmore, B.W.
AU - Yexley, Melissa
N1 - Export Date: 9 September 2020
PY - 2020/8/5
Y1 - 2020/8/5
N2 - A study of the charge conjugation and parity (CP) properties of the interaction between the Higgs boson and top quarks is presented. Higgs bosons are identified via the diphoton decay channel (H→γγ), and their production in association with a top quark pair (tt¯H) or single top quark (tH) is studied. The analysis uses 139 fb-1 of proton-proton collision data recorded at a center-of-mass energy of √s=13 TeV with the ATLAS detector at the Large Hadron Collider. Assuming a CP-even coupling, the tt¯H process is observed with a significance of 5.2 standard deviations. The measured cross section times H→γγ branching ratio is 1.64-0.36 +0.38(stat)-0.14+0.17(sys) fb, and the measured rate for tt¯H is 1.43-0.31+0.33(stat)-0.15+0.21(sys) times the Standard Model expectation. The tH production process is not observed and an upper limit on its rate of 12 times the Standard Model expectation is set. A CP- mixing angle greater (less) than 43 (-43)° is excluded at 95% confidence level.
AB - A study of the charge conjugation and parity (CP) properties of the interaction between the Higgs boson and top quarks is presented. Higgs bosons are identified via the diphoton decay channel (H→γγ), and their production in association with a top quark pair (tt¯H) or single top quark (tH) is studied. The analysis uses 139 fb-1 of proton-proton collision data recorded at a center-of-mass energy of √s=13 TeV with the ATLAS detector at the Large Hadron Collider. Assuming a CP-even coupling, the tt¯H process is observed with a significance of 5.2 standard deviations. The measured cross section times H→γγ branching ratio is 1.64-0.36 +0.38(stat)-0.14+0.17(sys) fb, and the measured rate for tt¯H is 1.43-0.31+0.33(stat)-0.15+0.21(sys) times the Standard Model expectation. The tH production process is not observed and an upper limit on its rate of 12 times the Standard Model expectation is set. A CP- mixing angle greater (less) than 43 (-43)° is excluded at 95% confidence level.
KW - article
KW - boson
KW - conjugation
KW - expectation
KW - hadron
KW - parity
KW - quark
U2 - 10.1103/PhysRevLett.125.061802
DO - 10.1103/PhysRevLett.125.061802
M3 - Journal article
VL - 125
JO - Physical review letters
JF - Physical review letters
SN - 1079-7114
IS - 6
M1 - 061802
ER -