Critical Reactions in Contemporary Nuclear Astrophysics

Nuclear reaction rates play a critical role in the understanding of stellar evolution and explosions. However, in many cases nuclear reaction rates still carry large uncertainties due to the paucity of experimental data and incomplete theoretical understanding of the underlying reaction mechanisms. New experimental methods and techniques, combined with the development of new theoretical tools, have exposed fresh avenues to pursue nuclear reactions of significance for nucleosynthesis at, or near, the actual temperatures of stellar burning. This review provides an overview of the most critical nuclear reactions for a number of nucleosynthesis environments. It also presents the current status of these reactions and provides insight into the specific uncertainties associated with the reaction rates. We identify existing shortcomings in the data and highlight the needs and opportunities for additional future experiments.