Nucleosynthesis models of the intermediate neutron-capture process

To understand the chemical history of our Universe abundances of elements heavier than iron are observed in the photospheres of old stars. The vast majority of heavy elements are formed by the slow (s) and rapid (r) neutron-capture processes. However, some observations of heavy-element abundance patterns of old stars are incompatible with either of these processes or even a combination of both. They can be explained as result of a separate neutron-capture process operating at neutron densities intermediate to the s and r process: the i process. Comparing i-process simulations with observed abundance patterns gives us insights into uncertain phases of stellar evolution and will ultimately help us understand the origin of the elements in our Universe.