Speaker
Description
We present extensions of previous studies using dimuon and wide-angle Bhabha events reconstructed in the main tracker to determine beam and center-of-mass energy observables at future electron–positron colliders. We evaluate the achievable precision on the luminosity-weighted center-of-mass energy and the individual electron and positron beam-energy parameters across operating points from the Z pole through Higgs-factory energies and beyond, for both ILC and FCC-ee.
We also investigate prospective monochromatized collision configurations and how the resulting beam-energy correlations and modified luminosity spectra affect these measurements. Finally, we discuss the tracker momentum-scale calibration and associated alignment, magnetic-field, and detector-control requirements needed for these kinematic methods to reach their optimal precision.