W Boson Polarisation at LEP2
The OPAL collaboration, G. Abbiendi, et al
TL;DR
This paper measures the spin density matrix elements of W bosons produced in electron-positron collisions at LEP2, analyzing their polarization states and searching for CP violation, confirming Standard Model predictions.
Contribution
It provides the first detailed measurement of W boson polarization states and CP symmetry in e+e- collisions at LEP2 energies.
Findings
W bosons are predominantly longitudinally polarized at 23.9%.
Results align with Standard Model predictions.
No evidence of CP violation was observed.
Abstract
Elements of the spin density matrix for W bosons in e+e- -> W+W- -> qqln events are measured from data recorded by the OPAL detector at LEP. This information is used calculate polarised differential cross-sections and to search for CP-violating effects. Results are presented for W bosons produced in e+e- collisions with centre-of-mass energies between 183 GeV and 209 GeV. The average fraction of W bosons that are longitudinally polarised is found to be (23.9 +- 2.1 +- 1.1)% compared to a Standard Model prediction of (23.9 +- 0.1)%. All results are consistent with CP conservation.
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.