An a0 resonance in strongly coupled πη, K K scattering from lattice QCD a0 RESONANCE in STRONGLY COUPLED ⋯ DUDEK, EDWARDS, and WILSON
| Autor: | Dudek, JJ, Edwards, RG, Wilson, DJ |
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| Přispěvatelé: | Wilson, David [0000-0003-2364-1161], Apollo - University of Cambridge Repository |
| Jazyk: | angličtina |
| Rok vydání: | 2016 |
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| Popis: | We present the first calculation of coupled-channel meson-meson scattering in the isospin $=1$, $G$-parity negative sector, with channels $\pi \eta$, $K\overline{K}$ and $\pi \eta'$, in a first-principles approach to QCD. From the discrete spectrum of eigenstates in three volumes extracted from lattice QCD correlation functions we determine the energy dependence of the $S$-matrix, and find that the $S$-wave features a prominent cusp-like structure in $\pi \eta \to \pi \eta$ close to $K\overline{K}$ threshold coupled with a rapid turn on of amplitudes leading to the $K\overline{K}$ final-state. This behavior is traced to an $a_0(980)$-like resonance, strongly coupled to both $\pi \eta$ and $K\overline{K}$, which is identified with a pole in the complex energy plane, appearing on only a single unphysical Riemann sheet. Consideration of $D$-wave scattering suggests a narrow tensor resonance at higher energy. This is the author accepted manuscript. The final version is available from the American Physical Society via http://dx.doi.org/10.1103/PhysRevD.93.094506 |
| Databáze: | OpenAIRE |
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