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Selected Topics in Top Quark Physics

J. G. Körner
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Abstract

I discuss three different selected topics in top quark physics. The first topic concerns the next-to-next-to-leading order calculation of the hadroproduction of top quark pairs and the role of multiple polylogarithms in this calculation. I report on an ongoing next-to-next-to-leading order calculation of heavy quark pair production in hadron collisions where the loop--by--loop part of the calculation is about to be completed. Calculating the loop-by-loop part allows one to take a glimpse at the mathematical structure of the full NNLO calculation. The loop-by-loop contributions bring in a new class of functions introduced only eight years ago by the Russian mathematician Goncharov called multiple polylogarithms. The second topic concerns a next-to-leading order calculation of unpolarized top quark decays which are analyzed in cascade fashion $t \to b + W^+$ followed by $W^+ \to l^+ + ν_l$. Finally, I present some next-to-leading order results on polarized top quark decays which are analyzed in the top quark rest system.

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J. G. Körner. 2006-09-05. Selected Topics in Top Quark Physics. https://doi.org/10.1142/9789812770523_0019

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