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CP Conserving and CP Violating Asymmetries in $e^+e^-\to t\bar tν_e\barν_e$} at the NLC: Application to Determining the Higgs Width

David Atwood·Amarjit Soni
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Abstract

The polarization asymmetries of $t$, $\bar t$ quarks can be used in the reaction $e^+e^-\to t\bar tν_e\barν_e$ to measure the Higgs width, in the Standard Model or in its extensions, and to search for non-standard CP violating phases. As an application of the CPT theorem the Higgs width is monitored through a CP-even, $T_N$-odd, polarization asymmetry, $B_y$. CP violation manifests through interference at tree graph level with the resonant Higgs amplitude. Consequently, the asymmetries are all quite sizable and can be in the range of 10--50\% for a wide choice of the Higgs mass.

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David Atwood, Amarjit Soni. 1996-07-31. CP Conserving and CP Violating Asymmetries in $e^+e^-\to t\bar tν_e\barν_e$} at the NLC: Application to Determining the Higgs Width. https://arxiv.org/abs/hep-ph/9607481

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