ar X iv : h ep - p h / 93 06 20 1 v 1 1 J un 1 99 3 HEAVY QUARK FRAGMENTATION INTO HEAVY
نویسندگان
چکیده
We present a QCD based interpretation of heavy quark fragmentation which utilizes the heavy quark mass expansion. By distinguishing between perturbative and non-perturbative QCD effects, we show how to reliably extract mass independent parameters characterizing the fragmentation function. Because these parameters are quark mass independent, this procedure should permit tests of heavy quark symmetry. Furthermore, we show that heavy quark mass corrections vanish at order m 2 /Q 2 in QCD. There also exist higher twist corrections of order Λm/Q 2 and α QCD π m 2 Q 2 ln(Q 2 /m 2) which we relate to the leading twist fragmentation function.
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