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arXiv · 1512.00140

Hamiltonian effective field theory study of the $\mathbf{N^*(1535)}$ resonance in lattice QCD

Zhan-Wei Liu·Waseem Kamleh·Derek B. Leinweber·Finn M. Stokes·Anthony W. Thomas·Jia-Jun Wu
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Abstract

Drawing on experimental data for baryon resonances, Hamiltonian effective field theory (HEFT) is used to predict the positions of the finite-volume energy levels to be observed in lattice QCD simulations of the lowest-lying $J^P=1/2^-$ nucleon excitation. In the initial analysis, the phenomenological parameters of the Hamiltonian model are constrained by experiment and the finite-volume eigenstate energies are a prediction of the model. The agreement between HEFT predictions and lattice QCD results obtained on volumes with spatial lengths of 2 and 3 fm is excellent. These lattice results also admit a more conventional analysis where the low-energy coefficients are constrained by lattice QCD results, enabling a determination of resonance properties from lattice QCD itself. Finally, the role and importance of various components of the Hamiltonian model are examined.

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Zhan-Wei Liu, Waseem Kamleh, Derek B. Leinweber, Finn M. Stokes, Anthony W. Thomas, Jia-Jun Wu. 2016-02-29. Hamiltonian effective field theory study of the $\mathbf{N^*(1535)}$ resonance in lattice QCD. https://doi.org/10.1103/physrevlett.116.082004

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