Speaker
Description
We describe the extension of the relativistic field theoretic finite-volume formalism to $N \pi \pi$ scattering states at maximal isospin, $I=5/2$, focusing on the new features that arise in this system.
We illustrate the application of the formalism by providing a sample numerical application that includes the $\Delta$ resonance in the $N\pi$ subchannel.
We study the singularities in $N\pi\pi$ amplitudes arising from $N\pi\pi\pi$ intermediate states, and find that our subthreshold cutoff functions must be modified to avoid such singularities.
This is a step on the way to a formalism for the $I=1/2$ (Roper) channel,
which will require the inclusion of mixing with $N\pi$ states.
We explain why these cannot be included by treating the nucleon as a pole in $p$-wave $N\pi$ scattering, an approach that has been successful in studying $D D^*$ scattering using the three-particle $DD\pi$ formalism.
| Parallel Session (for talks only) | Hadronic and nuclear spectrum and interactions |
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