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arXiv · hep-lat/9412087

Fitting Correlated Hadron Mass Spectrum Data

C. Michael·A. McKerrell
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Abstract

We discuss fitting hadronic Green functions versus time $t$ to extract mass values in quenched lattice QCD. These data are themselves strongly correlated in $t$. With only a limited number of data samples, the method of minimising correlated $χ^2$ is unreliable. We explore several methods of modelling the correlations among the data set by a few parameters which then give a stable and sensible fit even if the data sample is small. In particular these models give a reliable estimate of the goodness of fit.

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C. Michael, A. McKerrell. 1994-12-19. Fitting Correlated Hadron Mass Spectrum Data. https://doi.org/10.1103/physrevd.51.3745

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