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arXiv · 0710.0306

Unitary Isobar Model - MAID2007

D. Drechsel·S. S. Kamalov·L. Tiator
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Abstract

The unitary isobar model MAID2007 has been developed to analyze the world data of pion photo- and electroproduction. The model contains both a common background and several resonance terms. The background is unitarized according to the K-matrix prescription, and the 13 four-star resonances with masses below 2 GeV are described by appropriately unitarized Breit-Wigner forms. The data have been analyzed by both single-energy and global fits, and the transverse and longitudinal helicity amplitudes have been extracted for the four-star resonances below 2 GeV. Because of its inherent simplicity, MAID2007 is well adopted for predictions and analysis of the observables in pion photo- and electroproduction.

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D. Drechsel, S. S. Kamalov, L. Tiator. 2007-10-01. Unitary Isobar Model - MAID2007. https://doi.org/10.1140/epja/i2007-10490-6

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