On the arithmetic determination of the trace

Let K be a number field, which is tame and non-totally real. In this article we give a numerical criterion, depending only on the ramification behavior of ramified primes in K, to decide whether or not the integral trace of K is isometric to the integral trace of another number field L. As a byproduct of our proofs here, and in contrast with our previous results for cubic fields of positive discriminant, we show that for cubic fields of negative discriminant isometry between integral traces is equivalent to equality of discriminants.