Measurements of heavy quark production in electron-positron
collisions are used to analyse the strong interactions between
quarks and anti-quarks. A scaling behaviour is observed in
distributions of the rapidity change of D*, B*, and B mesons.
From these distributions information is obtained on the hadron
formation time, effective quark masses, and the potential
between quark-antiquark pairs. Predictions for fragmentation
functions are presented.
Keywords: fragmentation, formation time, quark masses, strong