A Z-Monitor to Calibrate Higgs Production via Vector Boson Fusion with Rapidity Gaps at the LHC

We study central Z-boson production accompanied by rapidity gaps on either side as a way to gauge Higgs weak boson fusion production at the LHC. We analyse the backgrounds for the bb-decay mode and show that these can be substantially reduced. Special attention is paid to the evaluation of the gap survival factor, which is the major source of theoretical uncertainty in the rate of H and Z central production events with rapidity gaps.