PT Journal AU ATLAS Collaboration (Aaboud, Mea Alvarez Piqueras, D Barranco Navarro, L Cabrera Urban, S Castillo Gimenez, V Cerda Alberich, L Costa, MJ Escobar, C Estrada Pastor, O Fernandez Martinez, P Ferrer, A Fiorini, L Fuster, J Garcia, C Garcia Navarro, JE Gonzalez de la Hoz, S Higon-Rodriguez, E Jimenez Pena, J Lacasta, C Madaffari, D Mamuzic, J Marti-Garcia, S Melini, D Mitsou, VA Pedraza Lopez, S Rodriguez Bosca, S Rodriguez Rodriguez, D Romero Adam, E Salt, J Sanchez Martinez, V Soldevila, U Sanchez, J Valero, A Valls Ferrer, JA Vos, M TI Search for Heavy Higgs Bosons A/H Decaying to a Top Quark Pair in pp Collisions at root s=8 TeV with the ATLAS Detector SO Physical Review Letters JI Phys. Rev. Lett. PY 2017 BP 191803 EP 20pp VL 119 IS 19 DI 10.1103/PhysRevLett.119.191803 LA English AB A search for heavy pseudoscalar (A) and scalar (H) Higgs bosons decaying into a top quark pair (t (t) over bar) has been performed with 20.3 fb(-1) of proton-proton collision data collected by the ATLAS experiment at the Large Hadron Collider at a center-of-mass energy root s = 8 TeV. Interference effects between the signal process and standard model t (t) over bar production, which are expected to distort the signal shape from a single peak to a peak-dip structure, are taken into account. No significant deviation from the standard model prediction is observed in the t (t) over bar invariant mass spectrum in final states with an electron or muon, large missing transverse momentum, and at least four jets. The results are interpreted within the context of a type-II two-Higgs-doublet model. Exclusion limits on the signal strength are derived as a function of the mass m(A/H) and the ratio of the vacuum expectation values of the two Higgs fields, tan beta, for m(A/H) > 500 GeV. ER