Baryon Resonance Analysis from MAID *
نویسنده
چکیده
The unitary isobar model MAID2007 has been used to analyze the recent data of pion electroproduction. The model contains all four-star resonances in the region below W =2 GeV and both single-Q and Q dependent transition form factors could be obtained for the Delta, Roper, D13(1520), S11(1535), S31(1620), S11(1650), D15(1675), F15(1680) and P13(1720). From the complete world data base, including also π − data on the neutron, also Q dependent neutron form factors are obtained. For all transition form factors we also give convenient numerical parameterizations that can be used in other reactions. Furthermore, we show how the transition form factors can be used to obtain empirical transverse charge densities and our first results are given for the Roper, the S11 and D13 resonances.
منابع مشابه
Maid Analysis Techniques *
MAID is a unitary isobar model for a partial wave analysis of pion photoand electroproduction in the resonance region. It is fitted to the world data and can give predictions for multipoles, amplitudes, cross sections and polarization observables in the energy range from pion threshold up to W = 2 GeV and photon virtualities Q < 5 GeV. Using more recent experimental results from Mainz, Bates, B...
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