A numerical coincidence Dp of -0.000489 was found between the ratios of proton emission at 459-keV and cosmic background at 0.25-keV respect to proton and to electron proper energy respectively. Multiplying 459-keV and 0.25-keV by Dp, two more numerical coincidences were found with 0.1-keV background and 0.06-eV of neutrino energy, respectively. Global criticality phenomena plus c and G discontinued decreasing provoke small cyclical reorganization of particles and quanta originating background emissions every 30-Myr are propose. At the beginning of each cycle, gradually emissions from electrons lasting 0.1 Myr originate the 0.25-keV background and, a possible 459-keV background from proton emissions. At following cycle, the 459-keV quanta makes two emissions of 0.1-keV originating a diffuse background, and 0.25-keV quanta makes two of 0.06-eV originating the relic neutrinos. The Dp is a possible physical constant that characterize the threshold, which trigger cyclical phenomena at space and Earth every 30-Myr