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arXiv · 0907.0661

The N* Physics Program at Jefferson Lab

Volker D. Burkert
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Abstract

Recent measurements of nucleon resonance transition form factors with CLAS at Jefferson Lab are discussed. The new data confirm the assertion of the symmetric constituent quark model of the Roper as the first radial excitation of the nucleon. For the first time, the longitudinal transition amplitude to the S11(1535) was extracted from the data. New results on the transition amplitudes for the D13(1520) resonance are presented showing a rapid transition from helicity 3/2 dominance seen at the real photon point to helicity 1/2 dominance at higher Q2. I also discuss aspects of the JLab program to search for new excited nucleon states predicted by quark models.

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Volker D. Burkert. 2009-07-03. The N* Physics Program at Jefferson Lab. https://doi.org/10.1088/1674-1137/33/12/001

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