At a high energy $ep$ collider, such as the Large Hadron-Electron Collider (LHeC) which is being planned at CERN, one can access the $WWgamma$ vertex exclusively in charged current events with a radiated photon, with no interference from the $WWZ$ ve
rtex. We find that the azimuthal angle between the jet and the missing momentum in each charged current event is a sensitive probe of anomalous $WWgamma$ couplings, and show that for quite reasonable values of integrated luminosity, the LHeC can extend the discovery reach for these couplings beyond all present experimental bounds.
We investigate the impact of the latest data on Higgs boson branching ratios on the minimal model with a Universal Extra Dimension (mUED). Combining constraints from vacuum stability requirements with these branching ratio measurements we are able to
make realistic predictions for the signal strengths in this model. We use these to find a lower bound of 1.3 TeV on the size parameter $R^{-1}$ of the model at 95% confidence level, which is far more stringent than any other reliable bound obtained till now.
