First measurement of the induced proton polarization, P(n), in the C-12 (e, e'p) reaction

• Main Author: Woo, Rhett J.
• Format: Others
• Language: English
• Published: W&M ScholarWorks 1996
• Online Access: https://scholarworks.wm.edu/etd/1539623892; https://scholarworks.wm.edu/cgi/viewcontent.cgi?article=3802&context=etd

The induced proton polarization, {dollar}P\sb{lcub}n{rcub},{dollar} was measured with the newly commissioned Recoil-Proton Focal Plane Polarimeter (FPP) at the MIT-Bates Linear Accelerator Laboratory. Using the {dollar}\sp{lcub}12{rcub}{lcub}\rm C{rcub}(e,e\sp\prime\vec p){dollar} reaction, the measurement was performed in quasifree kinematics at a {dollar}Q\sp2{dollar} of 0.48 (GeV/c){dollar}\sp2.{dollar} A recoil-momentum range of 0-250 MeV/c was sampled. The induced polarization, which vanishes in the Plane Wave Impulse Approximation, is sensitive to the absorptive part of the central optical-potential as well as explicit spin dependent terms, especially those due to spin-orbit interactions. Theoretical analysis indicates that this observable is primarily sensitive to final state interactions. For the experiment, the final state interactions are modeled with optical potentials in the context of the Distorted Wave Born Approximation. The results for the p{dollar}\sb{lcub}3/2{rcub}{dollar} shell are in good agreement with calculations of J. J. Kelly. The s{dollar}\sb{lcub}1/2{rcub}{dollar} shell data indicates a possible deviation from the one-body calculation, however, the continuum contribution is large, positive and difficult to subtract out.