Show simple item record

dc.contributor.authorDuvall, Wade Sayeren_US
dc.date.accessioned2019-05-10T06:00:35Z
dc.date.available2019-05-10T06:00:35Z
dc.date.issued2017-11-15
dc.identifier.othervt_gsexam:13445en_US
dc.identifier.urihttp://hdl.handle.net/10919/89476
dc.description.abstractThe Qweak experiment has precisely determined the weak charge of the proton Qp w by measuring the parity-violating asymmetry in elastic electron-proton scattering at a low momentum transfer of Q2 = 0.0249 (GeV/c)2 . Qpw has a definite prediction in the Standard Model, and a value of sin2 θW can be extracted from it for comparison with other neutral current observables. Qweak measured the weak charge of the proton to be Qpw(P V ES) = 0.0719 ± 0.0045, which is consistent with the Standard Model value of Qp w(SM) = 0.0708 ± 0.0003. Qweak ran at the Thomas Jefferson National Accelerator Facility for two and a half years and was installed in experimental Hall C. A 180µA 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◦ to 11.6◦ and then passed through a magnetic spectrometer and onto quartz Čerenkov detector bars. A detailed description of the theory and motivation behind the Qweak experiment is given. An overview of the Qweak apparatus and an in-depth discussion of the luminosity monitor performance is presented. A general overview of the Qweak analysis is also presented, with a focus on the beamline background correction, the nonlinearity measurement, and the simulation to constrain error for a rescattering effect. Also detailed here is the final, unblinded Qweak result, which determined Qpw to 6.2% and provided the highest precision measurement of sin2θW at low energy.en_US
dc.format.mediumETDen_US
dc.publisherVirginia Techen_US
dc.rightsThis item is protected by copyright and/or related rights. Some uses of this item may be deemed fair and permitted by law even without permission from the rights holder(s), or the rights holder(s) may have licensed the work for use under certain conditions. For other uses you need to obtain permission from the rights holder(s).en_US
dc.subjectnuclear physicsen_US
dc.subjectelectromagneticen_US
dc.subjectelectroweaken_US
dc.subjectparity violationen_US
dc.subjectsymmetryen_US
dc.subjectprotonen_US
dc.subjectweak chargeen_US
dc.subjectQweaken_US
dc.titlePrecision Measurement of the Proton's Weak Charge using Parity-Violating Electron Scatteringen_US
dc.typeDissertationen_US
dc.contributor.departmentPhysicsen_US
dc.description.degreePHDen_US
thesis.degree.namePHDen_US
thesis.degree.leveldoctoralen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplinePhysicsen_US
dc.contributor.committeechairPitt, Mark Len_US
dc.contributor.committeememberHuber, Patricken_US
dc.contributor.committeememberSimonetti, John Hen_US
dc.contributor.committeememberPiilonen, Leo Een_US
dc.contributor.committeememberSharpe, Eric Ren_US


Files in this item

Thumbnail
Thumbnail

This item appears in the following Collection(s)

Show simple item record