DAWN GRAND MAP VESTA NEUTRON ABSORPTION V1.0

DCP varies linearly with the macroscopic thermal neutron absorption cross section of Vesta's regolith. An equation for converting tabulated DCP values to absorption units is provided in this document.

DCP was determined from thermal and epithermal neutron counting rates measured by the NASA Dawn mission's Gamma Ray and Neutron Detector (GRaND) while in low altitude mapping orbit, about 210 km from Vesta's surface. The measurements are representative of Vesta's bulk regolith composition to depths of a few decimeters with a spatial resolution of about 300-km full-width-at-half-maximum of arc length on the surface. The methods used to determine neutron absorption are described by PRETTYMANETAL2013.