2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/7199The mystery of the Dark energy is not just its smallness. The extreme fine tuning of its density in the Early Universe such that it permits galaxy formation before creating a new inflationary epoch is its other unexplained aspect. Here we propose a model based on the very slow decay of a Super Heavy Dark Matter (SDM), presumed candidate for the origin of the Ultra High Energy Cosmic Rays (UHECRs). A small part of the remnants energy is in the form of a scalar field which decoheres and behaves like a quintessence field. This model does not need a special form for the potential and a simple $ϕ^4$ theory or an axion like scalar is enough. The equation of state of the Dark Energy becomes very close to a cosmological constant and is very well consistent with observations.3 pages; To appear in the proceedings of the 10th Marcel Grossmann Conference, 22-27 July 2003, Rio de Janeiro, BrazilAstrophysicstext