$\mathcalCP$ odd anomalous interactions of Higgs boson in its production at photon colliders

Abstract. We discuss the potentialities of the study of ${\cal C}{\cal P}$ odd interactions of the Higgs boson with photons via its production at $\gamma\gamma$ and $e\gamma$ colliders. Our treatment of $H\gamma\gamma$ and $HZ\gamma$ anomalous interactions includes a set of free parameters, whose impact on physical observables has not been considered before. We focus on two reactions, $\gamma\gamma \to H$ and $e\gamma\to e H$, and introduce the polarization and/or azimuthal asymmetries that are particularly sensitive to specific features of the anomalies. We discuss the ways of disentangling the effects of physically different parameters of the anomalies and estimate what the magnitude of ${\cal C}{\cal P}$ violating phenomena is that can be seen in these experiments.