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arXiv · hep-ph/9905227

Large Extra Dimension Effects on the Spin Configuration of the Top Quark Pair at e^+ e^- Colliders

Kang Young Lee·H. S. Song·JeongHyeon Song·Chaehyun Yu
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Abstract

Large extra dimension effects on the spin configuration of the top quark pair at the $e^+ e^-\to t\bar{t}$ process are studied. It is shown that the TeV scale quantum gravity effects cause significant deviations from the Standard Model predictions for the spin configuration in the off-diagonal basis: they lead to substantial cross sections of the like-spin states of the top quark pair, which vanish in the SM; they weaken the pure dominance of the processes, the Up-Down (Down-Up) spin states for the left-handed (right-handed) beam. In addition it is shown that the angular cut $-0.5<\cosθ<0$ is very effective to determine the sign of the quantum gravity corrections.

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Kang Young Lee, H. S. Song, JeongHyeon Song, Chaehyun Yu. 1999-05-07. Large Extra Dimension Effects on the Spin Configuration of the Top Quark Pair at e^+ e^- Colliders. https://doi.org/10.1103/physrevd.60.093002

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