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arXiv · hep-ph/9708228

Flavor Changing Neutral Higgs Couplings and Top-Charm Production at Next Linear Collider

W. -S. Hou·G. -L. Lin·C. -Y. Ma
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Abstract

We explore the possibility of detecting flavor changing neutral Higgs couplings at the Next Linear Collider (NLC) through $e^+e^-\to ν_e\bar{ν_e} t\bar{c}$. In the framework of a general two-Higgs doublet model, we perform a complete calculation and find that $σ(e^+e^-\to ν_eν_e t\bar{c}, ν_e\bar{ν_e} {\bar t}c)$ could reach $\sim 9$ fb for $\sqrt{s}=2 TeV$. This amounts to an annual production of 500 $t\bar{c}$ plus $\bar{t}c$ pairs at the NLC with an integrated luminosity of 50 fb$^{-1}$. The dependence of $tc$-production rate on the neutral scalar mixing angle is mild except when $\sin^2α\to 0 or 1$. The $ννW^+W^-$ background should be manageable after $b$-tagging, while $ννt\bar t$ background should not be a problem when the signal event rate is still interesting. The process, together with $e^+e^-\to ν_e\bar{ν_e} W^+W^-, ν_e\bar{ν_e} ZZ$ studies, offer the chance of measuring the $t$-$c$-Higgs coupling.

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BibTeXRIS

W. -S. Hou, G. -L. Lin, C. -Y. Ma. 1997-08-11. Flavor Changing Neutral Higgs Couplings and Top-Charm Production at Next Linear Collider. https://doi.org/10.1103/physrevd.56.7434

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