The process has to occur in very high-temperature environments (above 10 kelvins) so that the protons can overcome the large Coulomb barrier for charged-particle reactions. A hydrogen-rich environment is also a prerequisite due to the large proton flux needed. The seed nuclei needed for this process to occur are thought to be formed during breakout reactions from the hot CNO cycle. Typically proton capture in the rp-process will compete with (α,p) reactions, as most environments with a high flux of hydrogen are also rich in helium. The time scale for the rp-process is set by β decays at or near the proton drip line, because the weak interaction is notoriously slower than the strong interaction and electromagnetic force at these high temperatures.