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Holmes-Siedle, A.

Publications and source records attributed to Holmes-Siedle, A..

10 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1971

Study to determine and improve design for lithium-doped solar cells

Solar cell experiments show that a single lithium density parameter, the lithium density gradient, calculated from nondestructive capacitance measurements, provides the basis for accurate predictions of lithium cell behavior in a 1-MeV electron environment for fluences ranging between 3 X 10 to the 13th power e/sq cm and 3 X 10 to the 15th power/e sq cm. The oxygen-rich (quartz crucible) lithium cell with phosphorous starting dopant and lithium gradient between approximately 5 X 10 to the 18th power and 1.5 x 10 to the 19th power/cm to the 4th power was found superior in performance to the commercial 10 ohm-cm n/p control cells. Post-recovery stability of oxygen-rich cells was satisfactory. An average post-recovery current drop of approximately 1 mA was observed for 70 crucible cells after 1 year-equivalent storage time at 80 C. In contrast the oxygen-poor (float zone and Lopex) lithium cells displayed spotty initial performance and stability problems at room temperature.

Brucker, G.↗
NASA NTRS1971

Subsystem radiation susceptibility analysis for deep-space missions

Scientific, unmanned spacecraft on mission to Jupiter and beyond will be subjected to nuclear radiation from the natural environment and onboard nuclear power sources which may be harmful to subsystems. This report postulates these environments and discusses practical considerations to ensure confidence that the spacecraft's materials and subsystems will withstand the effects of anticipated radiation. Degradation mechanisms are discussed.

West, W. S.↗