Extracting the top-quark mass and Yukawa coupling from the threshold scan at CLIC

The Compact Linear Collider (CLIC) is a concept for a next-generation
machine at CERN, colliding electrons and positrons at energies up to
several TeV. One of the main goals at the initial CLIC running stage is
the measurement of the top-quark mass and width in a scan of the beam
energy through the pair production threshold. However, the shape of the
threshold cross section depends not only on the top-quark mass but also
on other model parameters as the top-quark width, top Yukawa coupling
and the strong coupling constant.

We study the expected precision of the top-quark mass determination from
the threshold scan. We use the most general fit approach with all
relevant model parameters taken into account. In addition, we take the
normalisation uncertainty into account as well as the expected
constraints on the top-quark mass, Yukawa coupling and strong coupling
constant from earlier experiments. We demonstrate that even in the most
general approach the top-quark mass can be extracted with a statistical
precision of the order of 30 MeV. Additional improvement is expected if
the running scenario is optimized.