Speaker
Description
The physics program of the Higgs factory is expected to focus on measurements of the 125 GeV Higgs boson, with the Higgs-strahlung process, production of the Higgs boson together with the Z boson, being the dominant production channel at 250 GeV. However, production of an extra light scalar in an analogous scalar-strahlung process is still not excluded by the existing experimental data, provided its coupling to the gauge bosons is sufficiently suppressed. Couplings of a new scalar could also be very different from the SM predictions leading to non-standard decay paterns. From the analysis strategies considered so far, searches for scalar decays to tau-lepton pairs seem to result is the strongest limits on the production cross section times the branching ratio. In my talk, I will present results from the recent study addressing searches for new scalar in this decay channel at the International Large Detector (ILD) experiment at the International Linear Collider (ILC) running at 250 GeV and 550 GeV. The study has been carried out in the framework of the ILD concept group and is based on the large samples of SM background processes from Geant4 full simulation and SGV fast simulation produced within the ILD.