Explaining 750 GeV diphoton excess from top/bottom partner cascade decay in two-Higgs-doublet model extension
Xiao-Fang Han (Department of Physics, Yantai University, Yantai, 264005, China); Lei Wang (Department of Physics, Yantai University, Yantai, 264005, China, IFIC, Universitat de València-CSIC, Apt. Correus 22085, València, E-46071, Spain); Lei Wu (ARC Centre of Excellence for Particle Physics at the Terascale, School of Physics, The University of Sydney, NSW, 2006, Australia); Jin Min Yang (Institute of Theoretical Physics, Academia Sinica, Beijing, 100190, China, Department of Physics, Tohoku University, Sendai, 980-8578, Japan); Mengchao Zhang (Institute of Theoretical Physics, Academia Sinica, Beijing, 100190, China)
In this paper, we interpret the 750 GeV diphoton excess in the Zee–Babu extension of the two-Higgs-doublet model by introducing a top partner ( T )/bottom partner ( B ). In the alignment limit, the 750 GeV resonance is identified as the heavy CP-even Higgs boson ( H ), which can be sizably produced via the QCD process pp→TT¯ or pp→BB¯ followed by the decay T→Ht or B→Hb . The diphoton decay rate of H is greatly enhanced by the charged singlet scalars predicted in the Zee–Babu extension and the total width of H can be as large as 7 GeV. Under the current LHC constraints, we scan the parameter space and find that such an extension can account for the observed diphoton excess.
