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Document Type

Open Access Dissertation

Degree Name

Doctor of Philosophy (PhD)

Degree Program

Physics

Year Degree Awarded

Fall 2014

First Advisor

Dr. Krishna Kumar

Second Advisor

Dr. Andrea Pocar

Third Advisor

Dr. John Dubach

Subject Categories

Nuclear | Plasma and Beam Physics

Abstract

The Lead Radius Experiment (PREX) was carried out in order to provide a model independent measurement of the RMS radius √ < r2 >of the neutron distribution in the 208Pb nucleus. The parity-violating scattering asymmetry for longitudinally polarized 1.06 GeV electrons from an unpolarized 208Pb target was measured at Q2 = 0.00880 GeV2. This measurement was performed by the PREX collaboration in Hall A at Jefferson Laboratory in Newport News, VA, between March and June, 2010. The electron detectors used in this measurement were designed and fabricated by University of Massachusetts-Amherst and Smith College. The resulting parity-violating asymmetry was measured as APV = 656±60(stat.)±14(sys.) ppb. This asymmetry extrapolates to a difference in radii between the nuclear neutron and proton distributions of √ < r2n >- √ < r2p >=0.33 +0.16 −0.18 fm.

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