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Colloquium: Final Results from the QWeak Experiment: A search for physics beyond the Standard Model via a measurement of the proton's weak charge.

Date:
-
Location:
CP 155
Speaker(s) / Presenter(s):
Professor Michael Gericke (University of Manitoba)
The QWeak collaboration completed a two year long, high precision measurement of the parity violating asymmetry in the elastic scattering of 1.1 GeV, longitudinally polarized electrons from protons. At low momentum transfer the measured asymmetry is directly related to the weak charge of the proton QWp = 1 - 4 sin2θW. The Standard Model makes a firm prediction for the size of the weak charge, based on the running of the weak mixing angle sin2θW so that QWeak provides a sensitive test for physics beyond the Standard Model, with a mass scale sensitivity up to several TeV. I will provide an overview of the experiment, including the measurement methodology and associated systematic effects. I will then present our final results for the proton weak charge, the weak mixing angle, and an extraction of the vector weak quark couplings C1u and C1d, using the 133Cs APV and QWeak measurements. I will also discuss the QWeak mass reach for new beyond-the-Standard-Model physics and briefly show our sensitivity to a few models.
Event Series: