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Measuring the QCD Gell Mann-Low $Ψ$-function

S. J. Brodsky·C. Merino·J. R. Pelaez
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Abstract

We present a general method for extracting the Gell Mann-Low logarithmic derivative of an effective charge of an observable directly from data as a mean for empirically verifying the universal terms of the QCD $β$-function. Our method avoids the biases implicit in fitting to QCD-motivated forms as well as the interpolation errors introduced by constructing derivatives from discrete data. We also derive relations between moments of effective charges as new tests of perturbative QCD.

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S. J. Brodsky, C. Merino, J. R. Pelaez. 1999-06-16. Measuring the QCD Gell Mann-Low $Ψ$-function. https://doi.org/10.1103/physrevd.60.114007

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