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arXiv · 1108.0780

Consistent interactions for high-spin baryons

Tom Vrancx·Lesley De Cruz·Jan Ryckebusch·Pieter Vancraeyveld
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Abstract

Consistent interactions for off-shell fermion fields of arbitrary spin are constructed from the gauge-invariance requirement of the interaction Lagrangians. These interactions play a crucial role in the quantum hadrodynamical description of high-spin baryon resonances in hadronic processes. We find that the power of the momentum dependence of a consistent interaction rises with the spin of the fermion field. This leads to unphysical structures in the energy dependence of the computed tree-level cross sections when the short-distance physics is cut off with standard hadronic form factors. A novel, spin-dependent hadronic form factor is proposed that suppresses the unphysical artifacts.

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Tom Vrancx, Lesley De Cruz, Jan Ryckebusch, Pieter Vancraeyveld. 2011-08-03. Consistent interactions for high-spin baryons. https://doi.org/10.1063/1.3701249

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