Top Spin Correlations in Theories with Large Extra-Dimensions at the Large Hadron Collider

In theories with large extra dimensions, we study the top spin correlations at the Large Hadron Collider. The s-channel process mediated by graviton Kaluza-Klein modes contributes to the top-antitop pair production in addition to the Standard Model processes, and affects the resultant top spin correlations. We calculated the full density matrix for the top-antitop pair production. With the fundamental scale of the extra dimensional theory below 2 TeV, we find a sizable deviation of the top spin correlations from the Standard Model one.