Spin Correlation intt¯Production frompp¯Collisions at√s=1.8TeV

The D0 collaboration has performed a study of spin correlation in $t\overline{t}$ production for the process $t\overline{t}\to {\mathrm{bW}}^{+}\overline{b}{W}^{-}$, where the $W$ bosons decay to $e\nu$ or $\mu \nu$. A sample of six events was collected during an exposure of the D0 detector to an integrated luminosity of approximately $125{\mathrm{pb}}^{-1\mathrm{}}$ of $\sqrt{s}=1.8\mathrm{}\mathrm{TeV}$ $p\overline{p}$ collisions. The standard model (SM) predicts that the short lifetime of the top quark ensures the transmission of any spin information at production to the $t\overline{t}$ decay products. The degree of spin correlation is characterized by a correlation coefficient $\kappa$. We find that $\kappa >-0.25\mathrm{}$ at the $68\%$ confidence level, in agreement with the SM prediction of $\kappa =0.88\mathrm{}$.