Effect of top quark spin on the unparticle couplings in yy -> t(t)over-bar

We investigate the potential of yy collisions to probe scalar unparticle couplings via top-antitop quark pair production. We find 95% confidence level limits on the unparticle couplings with an integrated luminosity of 500 fb(-1) and an energy of root s = TeV. We investigate the effect of the top quark spin polarization on the unparticle couplings. It is shown that spin polarization of the top quark leads to a significant improvement in the sensitivity limits.