This analysis studies the reaction ep → e′p′ϕ in the kinematical range 1.6 ≤ Q² ≤ 3.8 GeV² and 2.0 ≤ W ≤ 3:0 GeV at CLAS. After successful signal identification, total and differential cross sections are measured and compared to the world data set. Comparisons are made to the predictions of the Jean-Marc Laget(JML) model based on Pomeron plus 2-gluon exchange. The overall scaling of the total cross section was determined to be 1/Q<sup>4.6±1.7</sup> which is compatible within errors to the Vector Meson Dominance prediction of 1/Q⁴ as well as to the expected behavior of a quark and gluon exchange-dominated model described by Generalized Parton Distributions of 1/Q⁶. The differential cross section dσ/dφ was used to determine that the s-channel helicity conservation (SCHC) assumption is valid within the precision of the current data. SCHC leads to a simple expression for the decay angular distribution from which R, the ratio of the longitudinal to the transverse cross section, can be extracted. Under the assumption of SCHC, we determine R = 1.33 ± 0.18 at an average Q² of 2.21 GeV² which leads to a determination of the longitudinal cross section σ<sub>L</sub> = 5.3 ± 1.3 nb for exclusive ϕ production. / Ph. D.
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/28705 |
| Date | 27 August 2004 |
| Creators | Santoro, Joseph Peter |
| Contributors | Physics, Mizutani, Tetsuro, Pitt, Mark L., Tauber, Uwe C., Ficenec, John R., Smith, Elton |
| Publisher | Virginia Tech |
| Source Sets | Virginia Tech Theses and Dissertation |
| Detected Language | English |
| Type | Dissertation |
| Format | application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | JoeSantoroPHDThesis.pdf |
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