The Fermi motion contribution to J/ψ production at the hadron colliders

We investigate the relativistic Fermi motion effect in the case of J/ψ production in various hadron colliders. A light-cone wave function is adopted to represent the J/ψ final state. The change in the confinement parameter which sets a scale for the size of the final state, allows one to see the effect in an explicit manner. While the effect has considerable influence on the fragmentation probabilities and the differential cross sections, the total cross sections essentially are left unchanged. Such a feature is in agreement with the momentum sum rule which the fragmentation functions should satisfy.