Decay-lepton angular distribution in polarized $e^{+}{e}^{-}\to$ and $CP$-violating dipole couplings of the top quark

Abstract

In the presence of an electric dipole coupling of $t\bar{t}$ to a photon, and an analogous ``weak" dipole coupling to the $Z$, $CP$ violation in the process $e^{+}{e}^{-}\to t\bar{t}$ leads to the polarization of the top and anti-top. This polarization can be analyzed by studying the energy and angular distributions of a decay charged lepton (anti-lepton) when the top (anti-top) decays leptonically. We have obtained analytic expressions for these distributions when either $t$ or $\overline{t}$ decays leptonically. We study two types of simple $CP$-violating angular asymmetries which do not need tof simple $CP$-violating angular asymmetries which do not need the full reconstruction of the $t$ or $\bar{t}$. These together can help to determine the electric and weak dipole form factors independently. We have also shown how the use of longitudinal beam polarization can help to do this with only one asymmetry measurement, and to imprhelp to do this with only one asymmetry measurement, and to improve the sensitivity.

18 pages, latex, 3 figures will be added soon

References in corpus (4)

• Observation of Top Quark Production in Pbar-P Collisions
• Observation of the Top Quark
• CP-violating asymmetries in top-quark production and decay in $e^{+}{e}^{-}$ annihilation within the MSSM
• Helicity-Flip Bremsstrahlung and the Measurement of CP-Violating Form Factors in Polarized $e^{+}{e}^{-}$ Collisions

Cited by in corpus (22)

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• Constraints on supersymmetric soft phases from renormalization group relations
• New Hints for Testing Anomalous Top-Quark Interactions at Future Linear Colliders
• Angular distributions as a probe of anomalous ZZH and gammaZH interactions at a linear collider with polarized beams
• CP violation at a linear collider with transverse polarization
• CP Violation, Top Quarks and the Tevatron Upgrade
• $t\to bW$ in NonCommutative Standard Model
• Probing Top-Quark Couplings at Polarized NLC
• Electric dipole moment of top quark and CP-violating asymmetries in gamma gamma -> t tbar
• CP violation in tbW couplings at the LHC
• CP violating angular asymmetries of b and bbar quarks in e+e- -> t tbar
• Decay-lepton correlations as probes of anomalous ZZH and gammaZH interactions in e+e- --> ZH with polarized beams
• Charged lepton distributions as a probe of contact e+e-HZ interactions at a linear collider with polarized beams
• Probe of CP Violation in e+e- -> ttbar Near Threshold
• Effect of top quark spin on the unparticle couplings in γγ\to t\bar{t}
• Two-particle kinematic distributions from new physics at an electron-positron collider with polarized beams
• CP Violation in $\gamma \gamma \to t\bar{t}$ within the Minimal Supersymmetric Standard Model
• Determining Top Quark CP Violating Dipole Couplings from $e^{+}{e}^{-}\to t\bar{t}$
• Effective fermion-Higgs interactions at an $e^{+}{e}^{-}$ collider with polarized beams
• Decay-lepton angular distributions in e+e- -> t tbar to O(alpha_s) in the soft-gluon approximation
• Remark on CP-violating Polarization Asymmetry of tt-bar via Anomalous Couplings to gamma and Z