2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/42790It is pointed out that the narrow charmonium state at 3871.8 MeV reported by the Belle collaboration is likely to be a $D\bar D^*$ deuteronlike meson-meson state called a deuson. It was predicted near the $D\bar D^*$ threshold over 10 years ago. Its spin-parity would be 0-+ or 1++ and an important decay mode should be via $D^0\bar D^{*0}$ to $D^0\bar D^0π^0$. Its width to that channel should then be of the order 50 keV. Note: A more detailed update of this unpublished note is in hep-ph/0402237.4 pages. A more detailed update of this unpublished note is in hep-ph/0402237High Energy Physics - Phenomenologytext