2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/46156The Modified Leading Log Approximation of QCD and the local parton hadron duality picture are shown to give a fully satisfactory description of data on charged particle energy spectra in $e^+e^-$ annihilation. The analysis of data in terms of moments points out the running of $α_s$ both at very low $cms$ energy (${\cal O}$(3 GeV)) and at very low particle energy (${\cal O}$(200-500 MeV)). The study of the universal soft limit of energy spectra at low particle energy is proposed as a test of QCD coherence. The extension of this approach at identified particles' spectra is discussed.LaTeX, 4 pages, uses epsfig.sty and overcite.sty, to appear in Proc. XXXIst Rencontre de Moriond, ``QCD and High Energy Interactions'', Les Arcs, March 23rd-30th 1996High Energy Physics - Phenomenologytext