T-odd correlations in polarized top quark decays in the sequential decay t(↑) → X_b +W~+ (→?~+ + ν_?) and in the quasi-three-body decay t(↑) → X_b + ?~+ + ν_?

摘要

We identify the T-odd structure functions that appear in the description of polarized top quark decays in the sequential decay t(↑) → X_b + W~+(→?~+ + ν_?) (two structure functions) and the quasi-three-body decay t(↑) → X_b + ?~+ + ν_? (one structure function). A convenient measure of the magnitude of the T-odd structure functions is the contribution of the imaginary part Img_R of the right-chiral tensor coupling g_R to the T-odd structure functions which we work out. Contrary to the case of QCD, the NLO electroweak corrections to polarized top quark decays admit absorptive one-loop vertex contributions. We analytically calculate the imaginary parts of the relevant four electroweak one-loop triangle vertex diagrams and determine their contributions to the T-odd helicity structure functions that appear in the description of polarized top quark decays.