Top-quark spin correlation at Linear Colliders with anomalous couplings

Abstract

We investigate the feasibility of probing anomalous top-quark couplings of $Wtb$, $Zt\bar{t}$, and $\gamma t\bar{t}$ in terms of an effective Lagrangian with dimension-six operators at future $e^{+}{e}^{-}$ linear colliders with a c. m. energy $\sqrt{s}\sim 500-800$ GeV. We first examine the constraints on these anomalous couplings from the $Z\to b\bar{b}$ data at LEP I and from unitarity considerations. We then consider in detail the effects of anomalous couplings on $t\bar{t}$ spin correlations in the top-pair production and decay with three spin bases: the helicity, beamline and off-diagonal bases. Our results show that the polarized beams are more suitable for exploring the effects of different new operators. For polarized beams, the helicity basis yields the best sensitivity.

23 pages, 10 figures, references added

References in corpus (13)

• CP Violation in Top Physics
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• Effective description of quark mixing
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• $e^{+}{e}^{-}\to t\bar{t}H$ with Non-standard Higgs Boson Couplings
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• Azimuthal angular dependence of decay lepton in e+ e- --> t tbar
• CP violating Z t anti-t and gamma t anti-t Couplings at a Future e+ e- Collider

Cited by in corpus (14)

• Effects of genuine dimension-six Higgs operators
• Probing Electroweak Top Quark Couplings at Hadron Colliders
• CP violating anomalous top-quark couplings at the LHC
• A General Analysis of Wtb anomalous Couplings
• QCD Corrections to Static Heavy Quark Form Factors
• T-odd correlations from CP violating anomalous top-quark couplings revisited
• Improved Measurement of ttZ Couplings at the LHC
• Electroweak phase transition in the standard model with a dimension-six Higgs operator at one-loop level
• CP-odd correlations using jet momenta from tt_bar events at the Tevatron
• Probing top quark electromagnetic dipole moments in single-top-plus-photon production
• Searches for top-Higgs FCNC couplings via the Whj signal with $h\to \gamma \gamma$ at the LHC
• Non-universal gauge boson $Z^{\prime }$ and the spin correlation of top quark pair production at $e^{-}{e}^{+}$ colliders
• Effect of top quark spin on the unparticle couplings in γγ\to t\bar{t}
• Generalized top-spin analysis and new physics in $e^{+}{e}^{-}$ collisions with beam polarization