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arXiv · 0903.2314

Excited-State Effective Masses in Lattice QCD

George T. Fleming·Saul D. Cohen·Huey-Wen Lin·Victor Pereyra
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Abstract

We apply black-box methods, i.e. where the performance of the method does not depend upon initial guesses, to extract excited-state energies from Euclidean-time hadron correlation functions. In particular, we extend the widely used effective-mass method to incorporate multiple correlation functions and produce effective mass estimates for multiple excited states. In general, these excited-state effective masses will be determined by finding the roots of some polynomial. We demonstrate the method using sample lattice data to determine excited-state energies of the nucleon and compare the results to other energy-level finding techniques.

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George T. Fleming, Saul D. Cohen, Huey-Wen Lin, Victor Pereyra. 2009-03-13. Excited-State Effective Masses in Lattice QCD. https://doi.org/10.1103/physrevd.80.074506

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