  Precision measurements of the Drell-Yan (DY) cross section at the LHC
constrain new physics scenarios that involve new states with electroweak (EW)
charges. We analyze these constraints and apply them to models that can address
the LHC diphoton excess at 750 GeV. We confront these findings with LEP EW
precision tests and show that DY provides stronger constraints than the LEP
data. While 8 TeV data can already probe some parts of the interesting region
of parameter space, LHC14 results are expected to cover a substantial part of
the relevant terrain. We derive the bounds from the existing data, estimate
LHC14 reach and compare them to the bounds one gets from LEP and future FCC-ee
precision measurements.
