Beam Polarisation and Triple Gauge Couplings in ee\rightarrow WW at the ILC

Jenny List
2014 Proceedings of The European Physical Society Conference on High Energy Physics — PoS(EPS-HEP 2013)   unpublished
A unique feature of a future e + e − linear collider is the ability to provide longitudinal polarised beams. In order to fully exploit their benefits, the luminosity weighted average polarisation needs to be known with permille-level precision. Three complementary methods for measuring the beam polarisation from the collision data are presented. All studies are based on realistic full simulation of the ILD and SiD detector concepts. They include semi-leptonic and fully hadronic W -pair
more » ... n in e + e − annihilation at the ILC at centre-of-mass energies of 500 GeV and 1 TeV as well as all relevant physics and accelerator-related backgrounds. Assuming that the angular distributions of W -pair production are described by the Standard Model, the longitudinal polarisation of the electron and positron beams is measured with high accuracy. The W -pair events and the angular distributions for the semi-leptonic final state are also used to determine the triple gauge couplings. Results from a simultaneous measurement of the beam polarisations and the TGCs show that they can be determined independently and thus the method would not be compromised by indirect contributions from physics beyond the Standard Model.
doi:10.22323/1.180.0233 fatcat:txp4mdp4p5a3dgfqfttwcpi2yi