Precision electroweak experiments and heavy physics: An update

Abstract

We update our previous global analysis of weak neutral current and $Z$ and $W$ data in which the parameters $h_V$ and $h_A$ associated with new heavy physics were constrained, by incorporating recent results on $Z$ properties and $M_W$. We obtain $-0.93<h_V<0.33\mathrm{}$, $-1.9<h_{\mathrm{AZ}}<0.27\mathrm{}$, and $-2.5<h_{\mathrm{AW}}<1.5\mathrm{}$ at 90% C.L., considerably better than the previous limits.