Measuring the QCD Gell Mann - Low - function
نویسندگان
چکیده
We present a general method for extracting the Gell Mann-Low logarithmic derivative of an e ective charge of an observable directly from data as a mean for empirically verifying the universal terms of the QCD -function. Our method avoids the biases implicit in tting to QCD-motivated forms as well as the interpolation errors introduced by constructing derivatives from discrete data. We also derive relations between moments of e ective charges as new tests of perturbative QCD. Submitted to Physical Review D Research partially supported by the Department of Energy under contract DE-AC03-76SF00515 and the Spanish CICYT under contracts AEN-96-1673, AEN97-1693. yE-mail:[email protected]
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