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arXiv · 2002.12431

Dalitz plots and lineshape of $a_1(1260)$ from a relativistic three-body unitary approach

Daniel Sadasivan·Maxim Mai·Hakan Akdag·Michael Döring
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Abstract

We formulate the final state interaction of the $a_1(1260)$ resonance decay in a manifestly three-body unitary parameterization and fit it to the $a_1(1260)$ lineshape measured by the ALEPH experiment. Dalitz plots calculated from this fit are presented. The work demonstrates the feasibility to numerically solve a previously derived amplitude and its generalization to isobars with spin and coupled channels. The model can also be applied to other meson decays and modified for the finite-volume problem as it arises in lattice QCD due to its manifest unitarity.

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Daniel Sadasivan, Maxim Mai, Hakan Akdag, Michael Döring. 2020-02-27. Dalitz plots and lineshape of $a_1(1260)$ from a relativistic three-body unitary approach. https://doi.org/10.1103/physrevd.101.094018

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