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Beam polarization effects on top-pair production at the ILC

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 نشر من قبل Yoshimasa Kurihara
 تاريخ النشر 2017
  مجال البحث
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Full one-loop electroweak-corrections for an $e^-e^+rightarrow t bar{t}$ process associated with sequential $trightarrow b mu u_mu$ decay are discussed. At the one-loop level, the spin-polarization effects of the initial electron and positron beams are included in the total and differential cross sections. A narrow-width approximation is used to treat the top-quark production and decay while including full spin correlations between them. We observed that the radiative corrections due to the weak interaction have a large polarization dependence on both the total and differential cross sections. Therefore, experimental observables that depend on angular distributions such as the forward-backward asymmetry of the top production angle must be treated carefully including radiative corrections. We also observed that the energy distribution of bottom quarks is majorly affected by the radiative corrections.

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