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arXiv · 2401.06609

Incorporating $DD\pi$ effects and left-hand cuts in lattice QCD studies of the $T_{cc}(3875)^+$

Maxwell T. Hansen·Fernando Romero-López·Stephen R. Sharpe
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Abstract

We generalize the relativistic field-theoretic three-particle finite-volume scattering formalism to describe generic $DD\pi$ systems in the charm $C=2$ sector. This includes the isospin-0 channel, in which the recently discovered doubly-charmed tetraquark $T_{cc}(3875)^+$ is expected to manifest as a pole in the $DD \pi \to DD \pi$ scattering amplitude. The formalism presented here can also be applied to lattice QCD settings in which the $D^*$ is bound and, in particular, remains valid below the left-hand cut in $D D^*$ scattering, thus resolving an issue in previous analyses of lattice-determined finite-volume energies.

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Maxwell T. Hansen, Fernando Romero-López, Stephen R. Sharpe. 2024-01-12. Incorporating $DD\pi$ effects and left-hand cuts in lattice QCD studies of the $T_{cc}(3875)^+$. https://arxiv.org/abs/2401.06609

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