Atomic Parity-Violation and Precision Physics

The atomic parity-violation (APV) parameter QW for a nucleus with `n' neutrons and `z' protons has been included in the list of pseudo-observables accessible with the codes TOPAZ0 and ZFITTER. In this way one can add the APV results in the LEP EWWG `global' electroweak fits, checking the corresponding effect when added to the existing precision measurements.Comment: 9 Late

CP-Violatiing Asymmetries in e^+e^-\ra t\bar{t} with Longitudinally Polarized Elecrtons

New CP-violating asymmetries of decay leptons in e^+\,e^-\;\ra\;t\,\bar{t}, arising from electric and weak dipole couplings of $t\,\bar{t}$ to $\gamma$ and $Z$, are examined in the case of unpolarized and longitudinally polarized electrons. The new asymmetries measured together with the old ones can help to determine independently the real and imaginary parts of the electric as well as weak dipole couplings. Longitudinal beam polarization, if present, obviates the need for the simultaneous measurement of more than one asymmetry, and enhances considerably the sensitivity to the CP-violating parameters. Numerical results are presented for the Next Linear Collider with $\sqrt{s}=500$ GeV and $\int{\cal L}\,dt\;=\;10\,{\rm fb}^{-1}$.Comment: 12 pages LaTex,PRL-TH-94/3