TY - JOUR AU - ATLAS Collaboration (Aad, G. et al AU - Amos, K. R. AU - Aparisi Pozo, J. A. AU - Bailey, A. J. AU - Cabrera Urban, S. AU - Cantero, J. AU - Cardillo, F. AU - Castillo Gimenez, V. AU - Costa, M. J. AU - Didenko AU - Escobar, C. AU - Fiorini, L. AU - Fullana Torregrosa, E. AU - Fuster, J. AU - Garcia, C. AU - Garcia Navarro, J. E. AU - Gomez Delegido, A. J. AU - Gonzalez de la Hoz, S. AU - Gonzalvo Rodriguez, G. R. AU - Guerrero Rojas, J. G. R. AU - Higon-Rodriguez, E. AU - Lacasta, C. AU - Lozano Bahilo, J. J. AU - Marti-Garcia, S. AU - Martinez Agullo, P. AU - Miralles Lopez, M. AU - Mitsou, V. A. AU - Monsonis Romero, L. AU - Moreno Llacer, M. AU - Munoz Perez, D. AU - Navarro-Gonzalez, J. AU - Poveda, J. AU - Prades IbaƱez, A. AU - Rubio Jimenez, A. AU - Ruiz-Martinez, A. AU - Sabatini, P. AU - Salt, J. AU - Sanchez Sebastian, V. AU - Sayago Galvan, I. AU - Senthilkumar, V. AU - Soldevila, U. AU - Sanchez, J. AU - Torro Pastor, E. AU - Valero, A. AU - Valls Ferrer, J. A. AU - Varriale, L. AU - Villaplana Perez, M. AU - Vos, M. PY - 2023 DA - 2023// TI - Constraints on spin-0 dark matter mediators and invisible Higgs decays using ATLAS 13 TeV pp collision data with two top quarks and missing transverse momentum in the final state T2 - Eur. Phys. J. C JO - European Physical Journal C SP - 503 - 35pp VL - 83 IS - 6 PB - Springer AB - This paper presents a statistical combination of searches targeting final states with two top quarks and invisible particles, characterised by the presence of zero, one or two leptons, at least one jet originating from a b-quark and missing transverse momentum. The analyses are searches for phenomena beyond the Standard Model consistent with the direct production of dark matter in pp collisions at the LHC, using 139 fb(-1) of data collected with the ATLAS detector at a centre-of-mass energy of 13 TeV. The results are interpreted in terms of simplified dark matter models with a spin-0 scalar or pseudoscalar mediator particle. In addition, the results are interpreted in terms of upper limits on the Higgs boson invisible branching ratio, where the Higgs boson is produced according to the StandardModel in associationwith a pair of top quarks. For scalar (pseudoscalar) dark matter models, with all couplings set to unity, the statistical combination extends the mass range excluded by the best of the individual channels by 50 (25) GeV, excluding mediator masses up to 370 GeV. In addition, the statistical combination improves the expected coupling exclusion reach by 14% (24%), assuming a scalar (pseudoscalar) mediator mass of 10 GeV. An upper limit on the Higgs boson invisible branching ratio of 0.38 (0.30(-0.09)(+0.13)) is observed (expected) at 95% confidence level. SN - 1434-6044 UR - https://arxiv.org/abs/2211.05426 UR - https://doi.org/10.1140/epjc/s10052-023-11477-z DO - 10.1140/epjc/s10052-023-11477-z LA - English N1 - WOS:001187459300004 ID - ATLASCollaborationAad_etal2023 ER -