The first search for a heavy neutral spin-1 gauge boson (Z0
) with nonuniversal fermion couplings
produced via vector boson fusion processes and decaying to tau leptons or W bosons is presented. The
analysis is performed using LHC data at ffiffi
s p 1⁄4 13 TeV, collected from 2016 to 2018 with the CMS
experiment and corresponding to an integrated luminosity of 138 fb−1. The data are consistent with the
standard model predictions. Upper limits are set on the product of the cross section for production of the Z0
boson and its branching fraction to ττ or WW. The presence of a Z0 boson decaying to τþτ− (WþW−) is
excluded for masses up to 2.45(1.60) TeV, depending on the Z0 boson coupling to standard model weak
bosons, and assuming a Z0 → τþτ− (WþW−) branching fraction of 50%
