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The flavor-changing rare top decays $t\to c V V$ in topcolor-assisted technicolor theory

Chongxing Yue·Gongru Lu·Qingjun Xu·Guoli Liu·Guangping Gao
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Abstract

In the framework of topcolor-assisted technicolor (TC2) theory, we calculate the contributions of the scalars(the neutral top-pion $π_{t}^{0}$ and the top-Higgs $h_{t}^{0}$) to the flavor-changing rare top decays $t\to c V V$(V= W, g, $γ$ or Z). Our results show that $h_{t}^{0}$ can enhance the standard model $B_{r}^{SM}(t\longrightarrow cWW)$ by several orders of magnitude for most of the parameter space. The peak of the branching ratio resonance emerges when the top-Higgs mass is between $2m_{W}$ and $m_{t}$. The branching ratio $ B_{r}(t\to c W W)$ can reach $ 10^{-3}$ in the narrow range.

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Chongxing Yue, Gongru Lu, Qingjun Xu, Guoli Liu, Guangping Gao. 2001-03-08. The flavor-changing rare top decays $t\to c V V$ in topcolor-assisted technicolor theory. https://doi.org/10.1016/s0370-2693(01)00353-7

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