Sensitivity Study for the Observation of Spin Correlations in the $t\bar{t} \rightarrow$ lepton+jets channel

In this work, spin correlations between the top and the anti-top quark are investigated in a sensitivity analysis. For this purpose, the decay channel of $t\bar{t}\rightarrow$lepton+jets is considered and the strange quark is identified as a spin analyser next to the charged lepton using a $c$-tagging approach. Based on this, spin observables are constructed and analytical formulas are fitted to the distributions to obtain the spin coefficients. The reconstructed distributions are unfolded to the parton level and the sensitivity achieved is investigated considering systematic uncertainties. The best sensitivity was achieved for the $C(n, n)$ coefficient with a 31 $\sigma$ intervals distance to the no spin correlations value. The other coefficients have σ intervals of 3, 15 and 20 $\sigma$. In conclusion, a good sensitivity to spin correlations was reached.