We investigate the effects of extra neutral gauge bosons on the high Q2
region of the e+p→e+X cross section at s​=300 GeV. We found
that the only models with electroweak strength coupling, typical of extended
gauge theories, that give a better fit to the H1 and ZEUS high Q2 data than
the standard model, are ruled out by existing data from the Tevatron. From
general scaling arguments, using the allowed contact interactions, the only
allowed models with Z′'s would be those with strong couplings although even
in this case the statistical evidence is not compelling.Comment: Latex file uses revtex version 3, epsfig, 1 postscript figure is
attache