Using Heavy Quark Fragmentation into Heavy Hadrons to Determine QCD Parameters and Test Heavy Quark Symmetry∗

We present a detailed analysis of the use of heavy quark fragmentation into heavy hadrons for testing the heavy quark effective theory through comparison of the measured fragmentation parameters of the c and b quarks. Our analysis is entirely model independent. We interpret the known perturbative evolution in a way useful for exploiting heavy quark symmetry at low energy. We first show consistency with perturbative QCD scaling for measurements done solely with c quarks. We then apply the perturbative analysis and the heavy quark expansion to relate measurements from ARGUS and LEP. We place bounds on a nonperturbative quark mass suppressed parameter, and compare the values for the b and c quarks. We find consistency with the heavy quark expansion but fairly sizable QCD uncertainties. We also suggest that one might reduce the systematic uncertainty in the result by not extrapolating to low z. Submitted to: Nuclear Physics B This work is supported in part by funds provided by the U.S. Department of Energy (DOE) under contract #DEAC02-76ER03069, by the Texas National Research Laboratory Commission under grant #RGFY92C6, by the National Science Foundation under Grant No. PHY89-04035 and by CICYT (Spain) under grant #AEN 93-0234. National Science Foundation Young Investigator Award. Alfred P. Sloan Foundation Research Fellowship. Department of Energy Outstanding Junior Investigator Award.