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arXiv · 2301.03981

The L\"uscher scattering formalism on the $t$-channel cut

André Baião Raposo·Maxwell T. Hansen
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Abstract

The L\"uscher scattering formalism, the standard approach for relating the discrete finite-volume energy spectrum to two-to-two scattering amplitudes, fails when analytically continued so far below the infinite-volume two-particle threshold that one encounters the $t$-channel cut. This is relevant, especially in baryon-baryon scattering applications, as finite-volume energies can be observed in this below-threshold regime, and it is not clear how to make use of them. In this talk, we present a generalization of the scattering formalism that resolves this issue, allowing one to also constrain scattering amplitudes on the $t$-channel cut.

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André Baião Raposo, Maxwell T. Hansen. 2023-01-10. The L\"uscher scattering formalism on the $t$-channel cut. https://arxiv.org/abs/2301.03981

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