Publikace na Matematicko-fyzikální fakulta |
2011
Abstrakt
We measure the correlation between the spin of the top quark and the spin of the anti-top quark in t (t) over bar -} W(+)bW(-)(b) over bar -} l(+)vbl(-) (v) over bar(b) over bar final states produced in p (p) over bar collisions at a center of mass energy sqrt(s) = 1.96 TeV, where l is an electron or muon. The data correspond to an integrated luminosity of 5.4 fb(-1) and were collected with the D0 detector at the Fermilab Tevatron collider.
The correlation is extracted from the angles of the two leptons in the t and (t) over bar rest frames, yielding a correlation strength C = 0.10(-0.45)(+0.45). in agreement with the NLO QCD prediction within two standard deviations, but also in agreement with the no correlation hypothesis.