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Observing Spin Correlations in Single Top Production and Decay

Gregory Mahlon
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Abstract

The weak decay of a polarized top quark has a rich structure of angular correlations among its decay products. We describe some of the noteworthy features of such decays. We then examine the three modes of single top production, with an emphasis on the status of calculations of the degree and direction of polarization at Run II of the Tevatron. The associated production of a top quark with a W boson will be very difficult to observe at the Tevatron. Prospects for observing the other two production mechanisms are much better. The spin state of the produced top quark is understood at leading order in the W* production channel. For the Wg-fusion process, we present new results including the resummed logarithmic corrections of the form ln(mt^2/mb^2). The spin-dependence of the complete order alpha_s corrections to either of these processes has not yet been determined. The fraction of spin up top quarks is large (approx. 95%) for both modes provided that the appropriate spin quantization axis is chosen.

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Gregory Mahlon. 2000-11-28. Observing Spin Correlations in Single Top Production and Decay. https://arxiv.org/abs/hep-ph/0011349

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