Modeling of laboratory benchmarks for planetary nuclear spectroscopy

Planetary nuclear spectroscopy involves using the detection of gamma rays and neutrons from planetary surfaces to infer their elemental composition. Linking measured count rates to elemental abundances is a complex task that requires Monte Carlo modeling of the production, transport and detection of neutrons and gamma rays. This technique has been successfully used on planetary science missions to the Moon, Mercury, Mars, and the asteroids Eros, Ceres and Vesta. However, significantly better precision measurements are required to meet the science goals of future investigations including NASA’s Psyche mission to the asteroid of the same name, Dragonfly mission to Saturn’s Moon Titan and JAXA’s MMX mission to Mars’ moons.

In this talk I will provide an overview of recent benchmarking experiments and modeling that was conducted at the Johns Hopkins Applied Physics Laboratory in support of the upcoming Psyche, MMX and Dragonfly missions. These experiments have revealed that whilst there is reasonable agreement between measured data and simulations significant improvement is required, particularly in modeling gamma ray production, to meet the needs of near-term planetary nuclear spectroscopy investigations.