Joint Astrophysics Colloquium

Nuclear Astrophysics Sensitivities

Richard Cyburt

MSU

Nuclear astrophysics addresses questions related to the origin and evolution of the chemical elements, as well as astrophysical events powered by nuclear processes. Key to this exploration is reliable and up-to-date nuclear physics input. Of foremost importance in most astrophysical scenarios are thermonuclear reaction rates. These needs have driven many efforts into the systematization and formulation of reaction rate compilations as well as the exploration of reaction rate sensitivities in various astrophysical environments.

I will discuss reaction rate formalism and formulation, including JINA's efforts with the JINA REACLIB Project. I will describe how rates are used in astrophysical model calculations and how one can analyze the sensitivities of these models on reaction rates. I will use two examples to examine sensitivities: Big Bang Nucleosynthesis and Type I X-ray bursts. I review these astrophysical scenarios and how the resulting sensitivity studies guide research.

Community communication is highly important, as well as feedback on the user-inspired tools available online or for download. Nuclear astrophysics is a broad field, including areas of study in cosmology, stars and explosions on compact objects. Understanding the nuclear physics input and data needs for various astrophysical environments allows one to continually make improvements and keep the feedback cycle from model to experiment and ultimately removes dependence on nuclear uncertainties from the astrophysical problem.