Influence of anomalous VVh and VVhh on determination of higgs Self-Coupling

Abstract

The recent discovery of a Higgs boson at LHC, while establishing the Higgs mechanism as the way of electroweak symmetry breaking, started an era of precision measurements involving the Higgs boson. In an effective Lagrangian framework, we consider the e+e− → Zhh process, at an ILC at a center-of-mass energy of 800 GeV to investigate the effect of the ZZh and ZZhh couplings on the sensitivity of hhh coupling on this process. Our results show that the sensitivity of the trilinear Higgs self-coupling on this process has somewhat strong dependence on the Higgs-gauge boson couplings. Single and two parameter reach of ILC with an integrated luminosity of 1000 fb−1 are obtained on the effective couplings, c6 and cH, which are related to the hhh coupling. Further it is shown how these limits are affected by the presence of anomalous ZZh and ZZhh couplings. The kinematic distributions studied to understand the effect of anomalous couplings, again, show strong influence of Z-h couplings on the dependence of these distributions on hhh coupling.