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arXiv · 2107.03973

Three-body dynamics of the $a_1(1260)$ resonance from lattice QCD

Maxim Mai·Andrei Alexandru·Ruairí Brett·Chris Culver·Michael Döring·Frank X. Lee·Daniel Sadasivan
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Abstract

Resonant hadronic systems often exhibit a complicated decay pattern in which three-body dynamics play a relevant or even dominant role. In this work we focus on the $a_1(1260)$ resonance. For the first time, the pole position and branching ratios of a three-body resonance are calculated from lattice QCD using one-, two-, and three-meson interpolators and a three-body finite-volume formalism extended to spin and coupled channels. This marks a new milestone for ab-initio studies of ordinary resonances along with hybrid and exotic hadrons involving three-body dynamics.

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Maxim Mai, Andrei Alexandru, Ruairí Brett, Chris Culver, Michael Döring, Frank X. Lee, Daniel Sadasivan. 2021-07-08. Three-body dynamics of the $a_1(1260)$ resonance from lattice QCD. https://doi.org/10.1103/physrevlett.127.222001

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