Additional CP odd observables in Z decays

Recently, T-odd observables in Z-boson decays have been studied from the point of view of effective lagrangians. We consider additional CP-odd observables that appear in conjunction with absorptive phases. As an example we discuss the possibility of observing a CP violating energy asymmetry in the decays Z → BX and Z → anti BX, and we related this to the presence of an electroweak dipole moment of the b-quark. We estimate that expected LEP performance could yield a sensitivity to dipole moments of the order of 10-17 e cm. (orig.)