Conditions for liquid or icy core existence in KBO objects: Numerical simulations for Orcus and Quaoar

In this article, we present a model describing the thermal evolution and structure of Kuiper belt objects (KBO) as a function of the intensity of radiogenic heat sources, mean density and the object׳s formation time. We have studied numerically the dependence of the interior composition and structure of a forming body on the accretion rate and radionuclide content in the dust particles, as well as the impact of the radiogenic heat generation rate on the water phase transition dynamics. The model is applied to predict the present internal structure of Plutino (90482) Orcus and KBO (50000) Quaoar with special emphasis on the possibility of cryovolcanism.