Spin correlation in t(t)over-bar production from p(p)over-bar collisions at root s=1.8 TeV

Abstract

The D0 collaboration has performed a study of spin correlation in t (t) over tilde production for the process t (t) over bar --> bW(+)(b) over bar W-, where the W bosons decay to e nu or mu nu. A sample of six events was collected during an exposure of the DO detector to an integrated luminosity of approximately 125 pb(-1) of root s = 1.8 TeV p (p) over bar 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 (t) over bar decay products. The degree of spin correlation is characterized by a correlation coefficient kappa. We find that kappa > -0.25 at the 68% confidence level. in agreement with the SM prediction of kappa = 0.88.