Charmed-Hadron Fragmentation Functions from CERN LEP1 Revisited
Bernd A. Kniehl, Gustav Kramer
TL;DR
The work re-evaluates non-perturbative charmed-hadron fragmentation functions using OPAL LEP1 data with a starting scale mu0=m_Q to match modern PDF flavor thresholds. Through LO and NLO fits in the MS-bar scheme, it demonstrates that branching fractions and mean momentum fractions change only modestly, while the gluon fragmentation function is significantly enhanced at low x due to the scale shift. The updated FFs remain consistent with existing measurements and have been utilized in NLO hadroproduction analyses, reinforcing predictive power across e^+e^- and hadronic collisions. This study highlights the sensitivity of gluon FFs to the chosen starting scale and reinforces the universality of FFs under DGLAP evolution.
Abstract
In Phys. Rev. D 58, 014014 (1998) and 71, 094013 (2005), we determined non-perturbative D^0, D^+, D^{*+}, D_s^+, and Lambda_c^+ fragmentation functions, both at leading and next-to-leading order in the MS-bar factorization scheme, by fitting e^+e^- data taken by the OPAL Collaboration at CERN LEP1. The starting points for the evolution in the factorization scale mu were taken to be mu_0 = 2m_Q, where Q = c,b. For the reader's convenience, in this Addendum, we repeat this analysis for mu_0 = m_Q, where the flavor thresholds of modern sets of parton density functions are located.