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Publication Information
Title Precision Measurement of the Proton’s Weak Charge using Parity-Violating Electron Scattering
Abstract The Q_weak experiment has precisely determined the weak charge of the proton Q_w by measuring the parity-violating asymmetry in elastic electron-proton scattering at a low momentum transfer of Q^2 = 0.0249 (GeV/c)^2. Q_w^p has a definite prediction in the Standard Model, and a value of sin^2(theta_w) can be extracted from it for comparison with other neutral current observables. Q_weak measured the weak charge of the proton to be Q_w^p (PVES) = 0.0719 +/- 0.0045, which is consistent with the Standard Model value of Q_w^p (SM)= 0.0708 +/- 0.0003$. Q_weak ran at the Thomas Jefferson National Accelerator Facility for two and a half years and was installed in experimental Hall C. A 180 uA beam of longitudinally polarized electrons at 1.16 GeV scattered off a liquid hydrogen target of unpolarized protons. The electrons were collimated to an acceptance of 5.8 deg to 11.6 deg and then passed through a magnetic spectrometer and onto quartz Cherenkov detector bars. A detailed descrip
Author(s) Wade Duvall
Publication Date October 2017
Document Type Thesis
Primary Institution Virginia Polytechnic Inst. & State Univ., Blacksburg, VA
Affiliation Exp Nuclear Physics / Experimental Halls / Hall C
Funding Source Nuclear Physics (NP)
Proprietary? No
This publication conveys Literature Review and Summary
Document Numbers
JLAB Number: JLAB-PHY-17-2673 OSTI Number:
LANL Number: Other Number:
Associated with an experiment Yes
Experiment Number(s)
E08-016
Associated with EIC No
Supported by Jefferson Lab LDRD Funding No
Thesis
Thesis Type PhD
Advisor Institution
1. Mark L. Pitt (Virginia Tech)
Attachments/Datasets/DOI Link
Document(s)
Duvall_WS_D_2017.pdf (STI Document)
Dataset(s) (none)
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