Effects of a simulated high-energy space environment on the ultraviolet transmittance of optical materials between 1050 A and 3000 A.
Transmittances of LiF, MgF(2), CaF(2), BaF(2), Al(2)O(3), and fused SiO(2)were measured from 1050 A to 3000 A before and after irradiation by 10(14) electrons/cm(2) first at 1.0 MeV and then at 2.0 MeV. Similar measurements were made with 10(14) electrons/cm(2) at 2.0 MeV using A1(2)O(3) to shield fused SiO(2), ADP, calcite, and Corning glass filters 9-54 and 7-54 from the direct electron beam. The electron energy and dose represent what one might expect to encounter in the artificial radiation belt after one year in a circular, near polar orbit at 1400 km. From these measurements it is concluded MgF(2), BaF(2), and A1(2)O(3) have the greatest potential for space applications in the uv.
Heath
D F
DF
Goddard Space Flight Center, NASA,Greenbelt, Maryland, USA.
Sacher
P A
PA