The Influence of External UV Radiation Field on Primordial Gas Clouds: Formulation of the Problem

Our goal is to study the effects of the UV radiation from the first stars, quasars and decays of the hypothetical Super Heavy Dark Matter (SHDM) particles on the formation of primordial bound objects in the Universe. We trace the evolution of a spherically symmetric density perturbation in the Lambda Cold Dark Matter ($\Lambda$CDM) and MOND models, solving the frequency-dependent radiative transfer equation, non-equilibrium chemistry, and one-dimensional gas hydrodynamics. We concentrate on the destruction and formation processes of the H$_2$ molecule, which is the main coolant in the primordial objects.