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arXiv · 0905.0122

Pion Electroproduction Amplitude Relations in the 1/N_c Expansion

Richard F. Lebed·Lang Yu
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Abstract

We derive expressions for pion electroproduction amplitudes in the 1/N_c expansion of QCD, and obtain from them linear relations between the electromagnetic multipole amplitudes that hold at all energies. The leading-order relations in 1/N_c compare favorably with available data (especially away from resonances), but the next-to-leading-order relations tend to provide only small or no improvement.

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Richard F. Lebed, Lang Yu. 2009-10-12. Pion Electroproduction Amplitude Relations in the 1/N_c Expansion. https://doi.org/10.1103/physrevd.80.076006

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