Measuring the Gamma-Gamma Coupling of the Higgs at Linear Colliders

Observing the production of the Higgs particle in the $\gamma$-$\gamma$ mode of a linear $e^+e^-$ collider allows for the measurement of the $H\gamma\gamma$ coupling. We point out that for the intermediate Higgs mass range this measurement is considerably more challenging than previously believed. The $b \bar b$ signature receives a large background from the production of heavy quark pairs by resolved photons. We quantify the experimental requirements needed to make a meaningful measurement in the presence of this background.