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arXiv · 1710.07930

Pure spin-3/2 propagator for use in particle and nuclear physics

J. Kristiano·S. Clymton·T. Mart
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Abstract

We propose the use of pure spin-3/2 propagator in the $(3/2,0) \oplus (0,3/2)$ representation in particle and nuclear physics. To formulate the propagator in a covariant form we use the antisymmetric tensor spinor representation and we consider the $Δ$ resonance contribution to the elastic $πN$ scattering as an example. We find that the use of conventional gauge invariant interaction Lagrangian leads to a problem; the obtained scattering amplitude does not exhibit the resonance behavior. To overcome this problem we modify the interaction by adding a momentum dependence. As in the case of Rarita-Schwinger we find that a perfect resonance description could be obtained in the pure spin-3/2 formulation only if hadronic form factors were considered in the interactions.

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J. Kristiano, S. Clymton, T. Mart. 2017-10-22. Pure spin-3/2 propagator for use in particle and nuclear physics. https://doi.org/10.1103/physrevc.96.052201

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