Nuclear Hardening of Optical Coatings: Enhanced Energy Sharing Concept. Revision 1

摘要

Satellite component hardening requirements in the early 1970's led to the development of the enhanced energy sharing concept (EESC) for optical mirror coatings. The idea was to increase the survivability of aluminum coated fused silica mirrors to prompt energy deposition by interposing a thick layer of beryllium between the aluminum and the substrate. Separating the materials of higher Z by the low Z beryllium redistributes the deposited heat load over a larger volume and reduces the maximum temperature in the aluminum film. Theoretical analyses of heat transfer during and after an energy input pulse supported this concept and subsequent above-ground and underground tests confirmed the greater survivability of this mirror design. In the sections that follow we give an insight into the physical mechanisms responsible for nuclear radiation deposition and temperature rise. This is followed by a review of calculations of melt fluence for several mirror constructions taking into account only the dominant deposition mechanisms and heat flow. (ERA citation 11:036629)