P. Nason et Br. Webber, NONPERTURBATIVE CORRECTIONS TO HEAVY-QUARK FRAGMENTATION IN E(-) ANNIHILATION()E(), Physics letters. Section B, 395(3-4), 1997, pp. 355-363
We estimate the non-perturbative power-suppressed corrections to heavy
flavour fragmentation and correlation functions in e(+)e(-) annihilat
ion, using a model based on the analysis of one-loop Feynman graphs co
ntaining a massive, gluon. This approach corresponds to the study of i
nfrared renormalons in the large-n(f) limit of QCD, or to the assumpti
on of an infrared-finite effective coupling at low scales, We find tha
t the leading corrections to the heavy quark fragmentation function ar
e of order lambda/M, where lambda is a typical hadronic scale (lambda
similar to 0.4 GeV) and M is the heavy quark mass. The inclusion of hi
gher corrections corresponds to convolution with a universal function
of M(1 - x) concentrated at values of its argument of order lambda, in
agreement with intuitive expectations. On the other hand, corrections
to heavy quark correlations are very small,of the order of (lambda/Q)
(p), where Q is the centre-of-mass energy and p greater than or equal
to 2. (C) 1997 Elsevier Science B.V.