Anomalous gauge couplings of the Higgs boson at high energy photon colliders

Abstract

We study the sensitivity of testing the anomalous gauge couplings ${g}_{HVV}$'s of the Higgs boson in the formulation of linearly realized gauge symmetry via the processes $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}ZZ$ and $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}WWWW$ at polarized and unpolarized photon colliders based on ${e}^{+}{e}^{\ensuremath{-}}$ linear colliders of c.m. energies 500 GeV, 1 TeV, and 3 TeV. Signals beyond the standard model (SM) and SM backgrounds are carefully studied. We propose certain kinematic cuts to suppress the standard model backgrounds. For an integrated luminosity of $1\text{ }\text{ }{\mathrm{ab}}^{\ensuremath{-}1}$, we show that (a) $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}ZZ$ can provide a test of ${g}_{H\ensuremath{\gamma}\ensuremath{\gamma}}$ to the $3\ensuremath{\sigma}$ sensitivity of $O({10}^{\ensuremath{-}3}--{10}^{\ensuremath{-}2})\text{ }\text{ }{\mathrm{TeV}}^{\ensuremath{-}1}$ at a 500 GeV ILC, and $O({10}^{\ensuremath{-}3})\text{ }\text{ }{\mathrm{TeV}}^{\ensuremath{-}1}$ at a 1 TeV ILC and a 3 TeV CLIC, and (b) $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}WWWW$ at a 3 TeV CLIC can test all the anomalous couplings ${g}_{HVV}$'s to the $3\ensuremath{\sigma}$ sensitivity of $O({10}^{\ensuremath{-}3}--{10}^{\ensuremath{-}2})\text{ }\text{ }{\mathrm{TeV}}^{\ensuremath{-}1}$.