Results of Radiation-Induced Conductivity Testing of Europa Clipper Dielectric Materials

To quickly survey the charging characteristics of a wide range of dielectric materials being considered for use by the Europa Clipper spacecraft, JPL has developed a modified charge storage method test setup capable of measuring the magnitude of radiation-induced conductivity (RIC) and dark conductivity for up to 34 samples in parallel. We present material properties from a test campaign consisting of 129 measurements of 67 dielectric materials. In these measurements, bounding values of the RIC constant and dark conductivity ranged from 1.4 x middot10(-20) to 3.5 x middot10(-16) s/rad middot SZ middot cm and 2.2 x 10(-20) to 7.2 x 10(-18) (SZ middot cm)(-1), respectively, at 0 C-?. For most of the materials tested, the data presented here are the first RIC and the first in-vacuum conductivity results published for these materials. The implementation of the new test system is discussed in a separate paper.