Speaker
Description
High-energy $\gamma\gamma$- and $e\gamma$-collisions offer a rich phenomenological programme, complementary to $e^+e^-$ collisions at a linear collider both in kinematic as well as physics reaches. In particular, $\gamma\gamma$ collisions offer a unique setting to investigate properties of the Higgs boson(s). High polarisation of the photon beams (produced via Compton back-scattering) can be achieved and adjusted by flipping the polarisation of the incident laser. Furthermore, prospects for di-Higgs production at a $\gamma\gamma$ collider are particularly promising, and could open the way to a direct measurement of the trilinear Higgs self-coupling, at lower centre-of-mass energies than at an $e^+e^-$ collider.
In this talk we will present new results about the di-Higgs production process at the $\gamma\gamma$ collider, comparing different running tups. We will discuss the possibility of measuring the trilinear Higgs coupling, also making use of photon polarisations to disentangle different contributions to di-Higgs production.
