Perturbative description of inclusive energy spectra

The recent LEP-1.5 data on charged particle inclusive energy spectra are analyzed within the analytical QCD approach based on Modified Leading Log Approximation plus Local Parton Hadron Duality. The shape, the position of the maximum and the cumulants moments of the inclusive energy spectrum are well described within this model. The sensitivity of the results to the running of the coupling is pointed out. A scaling law for the one-particle invariant density $E dn/d^3p$ at small momenta is observed, consistently with the predictions of colour coherence in soft gluon bremsstrahlung.