Spin correlation in tt̄ production from pp̄ collisions at √s = 1.8 TeV

The D0 collaboration has performed a study of spin correlation in tt production for the process tt →bW + bW - , where the W bosons decay to eν or μν. A sample of six events was collected during an exposure of the D0 detector to an integrated luminosity of approximately 125pb -1 of √s=1.8TeV pp 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 tt decay products. The degree of spin correlation is characterized by a correlation coefficient κ. We find that κ>-0.25 at the 68% confidence level, in agreement with the SM prediction of κ=0.88.