Probing the HHH vertex in e+e-, e-gamma and gamma-gamma collisions for light and intermediate Higgs bosons

Abstract

We have studied double Higgs production at future linear colliders while paying special attention to the option of high-energy and high-luminosity photon beams. The main purpose was to examine the feasibility of e+e-, e-gamma and gamma-gamma colliders in order to probe the anomalous triple Higgs coupling, which is crucial for understanding the Standard Model. We considered mainly the cases of light and intermediate Higgs bosons. Double Higgs production is almost background free, except in the MH=MZ mass range, which is discussed separately. It is shown that for a light Higgs boson the HHH coupling can be measured even at e+e- collider at 500 GeV. For a intermediate Higgs boson a collider in the TeV region is suitable for such an investigation. We have estimated the bounds on the anomalous HHH coupling, which can be experimentally established using future linear colliders.