The Triple Higgs Boson Self-Coupling at Future Linear e+e-Colliders Energies: ILC and CLIC

Abstract

We analyzed the triple Higgs boson self-coupling al future e+e-colliders energies, with the reactions e+ e--+ bbHH, ttHH. We evaluate the total cross-sections for both bbHH and ttHH, and calculate the total number of events considering the complete set of Feynman diagrams at tree-level. We vary the triple coupling KA3H within the range K =: -1 and +2. The numerical computation is done for the energies expected to be available at a possible Future Linear e+e-Collíder with a center-of-mass energy 800, 1000, 1500GeV and a lurninosity 1000tb-1. Our analysis is also extended to a center-of-mass energy 3 Te V and luminosities of 1000 and 5000 tb-I. We found that foe the process e+e--+ bbHH, the complete calculatíon díffers only by 3% from the approximate calculatíon e+e--+ ZHH(Z -+ bb), while for the process e+e--+ ttHH, the expected number of events, considering the decay products of both t and H, is not enough to obtain an accurate determination of the triple Higgs boson self-coupling.