# TTP01-16 Top Quark Spin Correlations at Hadron Colliders: Predictions at Next-to-Leading Order QCD

TTP01-16 Top Quark Spin Correlations at Hadron Colliders: Predictions at Next-to-Leading Order QCD

TTP01-16 Top Quark Spin Correlations at Hadron Colliders: Predictions at Next-to-Leading Order QCD

The collider experiments at the Tevatron and the LHC will allow for detailed

   investigations of the properties of the top quark. This requires precise predictions of
the hadronic production of $t\bar t$ pairs and of their subsequent decays. In this
Letter we present for the reactions $p {\bar p}, p p \to t{\bar t} + X \to \ell^+\ell'^-X$
the first calculation of the dilepton angular distribution at next-to-leading order
(NLO) in the QCD coupling, keeping the full dependence on the spins of the
intermediate $t\bar{t}$ state. The angular distribution reflects the degree of
correlation of the $t$ and $\bar t$ spins which we determine for different choices of
$t$ and $\bar t$ spin bases. In the case of the Tevatron, the QCD corrections are
sizeable, and the distribution is quite sensitive to the parton content of the proton.
 W. Bernreuther, A. Brandenburg, Z. G. Si, P. Uwer Phys. Rev. Lett. 87 242002 2001 PDF PostScript arXiv