著者

原 和彦 金 信弘 大川 英希 佐藤 構二 受川 史彦 ATLAS Collaboration Hara K. Kim S.H. Okawa H. Sato K. Ukegawa F.

出版者

Elsevier B.V.

雑誌

Physics letters. B (ISSN:03702693)

巻号頁・発行日

no.759, pp.601-621, 2016-08

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Measurements of the W±→ℓ±ν and Z→ℓ+ℓ− production cross sections (where ℓ±=e±,μ±) in proton–proton collisions at √s=13 TeV are presented using data recorded by the ATLAS experiment at the Large Hadron Collider, corresponding to a total integrated luminosity of 81 pb−1. The total inclusive W±-boson production cross sections times the single-lepton-flavour branching ratios are σtotW+=11.83 ±0.02(stat)±0.32(sys)±0.25 (lumi) nb and σtotW−=8.79 ±0.02(stat)±0.24(sys)±0.18 (lumi) nb for W+ and W−, respectively. The total inclusive Z -boson production cross section times leptonic branching ratio, within the invariant mass window 66<mℓℓ<116 GeV, is σtotZ=1.981 ±0.007(stat)±0.038(sys)±0.042 (lumi) nb. The W+, W−, and Z -boson production cross sections and cross-section ratios within a fiducial region defined by the detector acceptance are also measured. The cross-section ratios benefit from significant cancellation of experimental uncertainties, resulting in σfidW+/σfidW−=1.295 ±0.003(stat)±0.010 (sys) and σfidW±/σfidZ=10.31 ±0.04(stat)±0.20 (sys). Theoretical predictions, based on calculations accurate to next-to-next-to-leading order for quantum chromodynamics and to next-to-leading order for electroweak processes and which employ different parton distribution function sets, are compared to these measurements.

著者

The ATLAS Collaboration Hara K. Kim S.H. Okawa H. Sato K. Ukegawa F.

出版者

Elsevier B.V.

雑誌

Physics letters. B (ISSN:03702693)

巻号頁・発行日

vol.765, pp.11-31, 2017-02

被引用文献数

23

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A search for dark matter pair production in association with a Higgs boson decaying to a pair of bottom quarks is presented, using 3.2 fb−1 of pp collisions at a centre-of-mass energy of 13 TeV collected by the ATLAS detector at the LHC. The decay of the Higgs boson is reconstructed as a high-momentum b¯b system with either a pair of small-radius jets, or a single large-radius jet with substructure. The observed data are found to be consistent with the expected backgrounds. Results are interpreted using a simplified model with a Z′Z′ gauge boson mediating the interaction between dark matter and the Standard Model as well as a two-Higgs-doublet model containing an additional Z′Z′ boson which decays to a Standard Model Higgs boson and a new pseudoscalar Higgs boson, the latter decaying into a pair of dark matter particles.