Vector boson fusion versus gluon fusion

Vector-boson fusion (VBF) is a clean probe of the electroweak-symmetry breaking (EWSB), which inevitably suffers from some level of contamination due to the gluon fusion (ggF). In addition to the jet variables used in the current experimental analysis, we analyze a few more jet-shape variables defined by the girth and integrated jet shape. Taking $H\ensuremath{\rightarrow}W{W}^{*}\ensuremath{\rightarrow}e\ensuremath{\nu}\ensuremath{\mu}\ensuremath{\nu}$ and $H\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\gamma}$ as examples, we perform the analysis with a new technique of the two-step boosted-decision-tree method, which significantly reduces the contamination of the ggF in the VBF sample, thus, providing a clean environment in probing the EWSB sector.