2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/45698Recent data from the Tevatron have revealed that the production rate of prompt charmonium is more than an order of magnitude larger than the best theoretical predictions of a few years ago. This surprising result can be understood by taking into account new production mechanisms that include fragmentation and the formation of charmonium from color-octet $c \bar c$ pairs.8 pages, LaTeXHigh Energy Physics - Phenomenologytext