Single decay-lepton angular distributions in polarized e+e- --> t tbar and simple angular asymmetries as a measure of CP-violating top dipole couplings

摘要: In the presence of an electric dipole coupling t-tbar to a photon, and analogous "weak" Z, CP violation in process e+e- --> t tbar results modified polarization top anti-top. This can be analyzed by studying angular distributions decay charged leptons when or anti-top decays leptonically. Analytic expressions are presented for these either leptonically, including O(alpha_s) QCD corrections soft-gluon approximation. The insensitive anomalous interactions decay. Two types simple CP-violating polar-angle asymmetries two azimuthal asymmetries, which do not need full reconstruction tbar, studied. Independent 90% CL limits that may obtained on real imaginary parts weak couplings at linear collider operating sqrt{s}=500 GeV with integrated luminosity 500 fb^{-1} also sqrt{s}=1000 1000 have been evaluated. effect longitudinal electron and/or positron beam polarizations has included.