The Evolution of Hadron Spectra in the Modified Leading Logarithm Approximation

Abstract

We perform fits of ${\Lambda }_{\mathrm{QCD}}$ and the gluon fragmentation function $D(x,Q)$ at initial scale $Q_0\gg {\Lambda }_{\mathrm{QCD}}$ to charged light hadron momentum spectra data by evolving in the Modified Leading Logarithm Approximation. Without additional assumptions, we achieve a good description of the available data for $\xi =\ln (1/x)$ up to and around the Gaussian peak, and values of ${\Lambda }_{\mathrm{QCD}}$ acceptably close to those in the literature. In particular, we find that this procedure describes the position of the peak, and, in contrast to the Limiting Spectrum, also the normalization.

Comments: To be published in Eur.Phys.J.C, EPJC040401