Measurement of spin correlations in tt production using the matrix element method in the muon+jets final state in pp collisions at √s=8 TeV

Abstract

The consistency of the spin correlation strength in top quark pair production with the standard model (SM) prediction is tested in the muon+jets final state. The events are selected from pp collisions, collected by the CMS detector, at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.7 fb−1. The data are compared with the expectation for the spin correlation predicted by the SM and with the expectation of no correlation. Using a template fit method, the fraction of events that show SM spin correlations is measured to be View the MathML source, representing the most precise measurement of this quantity in the muon+jets final state to date.