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Complete Relativistic Description of the N*(1520)

Lukas Jahnke·Stefan Leupold
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Abstract

A relativistic description of spin 3/2 resonances and their decay channels is presented by calculating their selfenergies and spectral functions. The full vector-spinor structure is taken into account. Special emphasis is put on the N*(1520) and its decay channels pi N, rho N and pi Δ. All interactions are formulated such that only the correct number of degrees of freedom of a spin 3/2 state is propagated. The obtained results are compared with several approximations frequently used to avoid the complicated vector-spinor structure. Since this structure is taken fully into account here, the quality of the approximations can be judged.

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Lukas Jahnke, Stefan Leupold. 2006-01-24. Complete Relativistic Description of the N*(1520). https://doi.org/10.1016/j.nuclphysa.2006.07.039

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