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arXiv · 2106.09031

An effective field theory of the Delta-resonance

Juan Carlos Criado·Abdelhak Djouadi·Niko Koivunen·Kristjan Müürsepp·Martti Raidal·Hardi Veermäe
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Abstract

We present an effective field theory of the $\Delta$-resonance as an interacting Weinberg's $(3/2,0)\oplus (0,3/2)$ field in the multi-spinor formalism. We derive its interactions with nucleons $N$, pions $\pi$ and photons $\gamma$, and compute the $\Delta$-resonance cross-sections in pion-nucleon scattering and pion photo-production. The theory contains only the physical spin-3/2 degrees of freedom. Thus, it is intrinsically consistent at the Hamiltonian level and, unlike the commonly used Rarita-Schwinger framework, does not require any additional ad hoc manipulation of couplings or propagators. The symmetries of hadronic physics select a unique operator for each coupling $N\pi\Delta$ and $\gamma\pi\Delta$. The proposed framework can be extended to also describe other higher-spin hadronic resonances.

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Juan Carlos Criado, Abdelhak Djouadi, Niko Koivunen, Kristjan Müürsepp, Martti Raidal, Hardi Veermäe. 2021-06-16. An effective field theory of the Delta-resonance. https://arxiv.org/abs/2106.09031

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