Experimental determination of interaction between the radiation fields of Dragonfly's MMRTG and Titan's environment I: Neutron results

Abstract

A pressure vessel was evacuated and filled with an analog Titan atmosphere, in which a source of neutrons was suspended. Readings were taken from a neutron detector in a moderator block below, with the source at various height within the chamber. Neutron attenuation by the atmosphere was not found to be statistically significant, and absorption by surface material was found to be most likely minimal, refuting and tentatively reinforcing the respective modelling conclusions. Ultimately it was found that neutrons from the MMRTG are unlikely to be a problem for Dragonfly's measurements on the surface of Titan, and neutronic modelling should have fidelity sufficient to determine the magnitudes of minor effects.