QCD at the Future Circular $\rm{e^{+}e^{-}}$ Collider

Abstract

The Future Circular Collider in the $\mathrm{e^{+}e^{-}}$ configuration offers the opportunity to significantly improve SM measurements with dedicated runs at the Z-pole, WW threshold, ZH (240 GeV), and $\mathrm{t}\bar{\mathrm{t}}$ threshold. With a factor of approximately $10^{5}$ more statistics at the Z-pole and $10^{4}$ at the WW threshold than at LEP, the FCC-ee will enable the extraction of the strong coupling $\alpha_{s}$ at the per-mille level. Parton showering studies exploiting the pure gluon sample from $\mathrm{ZH}({\rightarrow} \mathrm{gg})$ will greatly improve our understanding of gluon radiation and fragmentation, directly impacting quark vs gluon discrimination studies. Further possibilities include precision hadronization studies and colour reconnection studies at the WW threshold. Some elements of the rich precision QCD program of the FCC-ee are outlined below.