UNITARITY CONSTRAINTS ON ANOMALOUS TOP-QUARK COUPLINGS TO WEAK GAUGE BOSONS

If there is new physics associated with the top quark, it could show u p as anomalous couplings of the top quark to weak gauge bosons, such a s Zt(t) over bar and Wt (b) over bar vector and axial-vector couplings . We use the processes <t(t)over bar>-->Z(0)Z(0), <t(t)over bar>-->W+W -, and <t(t)over bar>-->Z(0)H to obtain the unitarity constraints on t hese anomalous couplings, and combine these constraints with those fro m precision electroweak data. The unitarity constraints can impose add itional limits on the anomalous couplings when the scale of new physic s is as low as 2 TeV. A nonzero measurement of such an anomalous coupl ing leads to an upper limit on the new physics scale from the unitarit y condition.