The directional, differential intensities of protons over the energy range ∼200 ev to 50 key injected into the outer radiation zone (i.e., the extraterrestrial ring current) coincident with the initial phase of the geomagnetic storm during early July 1966 were monitored with a sensitive array of electrostatic analyzers borne on the earth satellite OGO 3. Proton intensities are greatly enhanced throughout the outer radiation zone for L values ≳3 during the main phase of this moderate magnetic storm, and the injection mechanism ceases to be effective after the storm main phase for L values ≲5.5. Proton (30 ≤ E ≤ 50 kev) intensities are shown to exponentially decay with lifetimes ranging from 15 to 105 hours in substantial agreement with calculated lifetimes invoking measured charge‐exchange cross sections for protons incident upon atomic hydrogen and a model of the atomic hydrogen concentration in the earth's exosphere. The atomic hydrogen concentration model for the terrestrial exosphere providing the best fit to the observed proton lifetimes over geocentric radial distances 2.5–4.8 RE (corresponding to observed concentrations ∼200 to 30 hydrogen atoms/cm³) allows only atoms in ballistic orbits in the exosphere as opposed to a model geocorona that includes an additional atomic hydrogen population in captive elliptical orbits.

Measurements of the counting rates (∼103 to 104 counts/sec) of continuous-channel electron multipliers mounted in an electrostatic analyzer responding to a monoenergetic beam of electrons, while operating in a vacuum chamber at a pressure ∼3×10−6 Torr attained with an oil diffusion pump, display a degradation of their gain (fatigue) which is proportional to the accumulated counts. The useful lifetime of these devices when employed with fixed-threshold pulse amplifiers is defined here as the accumulated counts until gain degradation has produced a reduction of the counting rates to 15% of the initial responses at an operating bias voltage of 4000 V and constant stimuli. The lifetimes of these particle detectors in this laboratory environment are ∼1010 counts or, for example, an average counting rate of 300 counts/sec for one year. Comparison of this laboratory lifetime with the responses of similar instrumentation which has been flown on the earth satellites OGO's 3, 4, and 5 and IMP 4 demonstrates that the expected lifetimes for these electron multipliers in a spaceflight environment are several years. Efficiencies of an electron multiplier for counting monoenergetic electrons over an energy range ∼60 to 50 000 eV are also presented.

Commercialization of concentrating solar power (CSP) technologies require the development of advanced reflector materials that are low cost and maintain high specular reflectance for extended lifetimes under severe outdoor environments. During the past 9 years, the National Renewable Energy Laboratory (NREL) has funded Science Applications International Corporation (SAIC) in McLean, Virginia, to develop a promising low-cost advanced solar reflective material (ASRM) combining the best of both thin-glass and silvered-polymer reflectors. The alumina (Al2O3) coating is deposited by ion-beam-assisted physical vapor deposition (IBAD). Materials undergoing testing demonstrate excellent durability under accelerated and outdoor weathering. To help commercialize the technology, NREL had a cost analysis performed incorporating realistic web coating assumptions and the technical improvements made in the ASRM. The biggest process cost items are the alumina and machine burden (which collects the cost of the building and office staff). The switch from a polyethylene terethaphalate (PET) to a steel substrate for the ASRM is a significant contributor to the cost. The cost of high-purity alumina should drop from $400/kg to $200/kg when purchased in 20-kg quantities. Alumina deposition rate then becomes the critical cost driver. In a previous study, deposition rates above 100 nm/s were not examined, but deposition rates greater than 100 nm/s are being used routinely for thin alumina coatings deposited on commercial web-coaters as barrier coatings. In addition, multiple (2–3) Al2O3 IBAD zones can be used in one roll-coating machine to deposit thicker alumina at a lower web speed. This means that with increasing deposition rate and/or multiple zones, the total production cost of the SAIC ASRM with 1-μm thick Al2O3 on PET will meet both the 1992 cost goal of $10.76/m2 ($1/ft2) and the equivalent cost goal of $13.79/m2 ($1.31/ft2) when the 1992 cost goal is corrected for inflation. There is a minimum deposition rate needed to reach the cost goal and a maximum deposition rate related to the number of zones after which no significant cost gains are observed. These asymptotic total production costs are $8.06/m2 ($7.39/m2 excluding substrate) for a large commercial web-coating company and $7.62/m2 ($6.94/m2 excluding substrate) for a smaller company. As can be seen by these numbers, the $10.76/m2 cost goal can be reached, but the cost of the substrate is still a major consideration. In addition, the width of the web was increased from 600 to 1200 mm, which decreased the asymptotic total production costs. The results of the cost analysis will be described.

Commercialization of concentrating solar power (CSP) technologies require the development of advanced reflector materials that are low cost and maintain high specular reflectance for extended lifetimes under severe outdoor environments. During the past nine years, the National Renewable Energy Laboratory (NREL) has funded Science Applications International Corporation (SAIC) in McLean, Virginia, to develop a promising low-cost advanced solar reflective material (ASRM) combining the best of both thin-glass and silvered-polymer reflectors. The alumina Al2O3 coating is deposited by ion-beam-assisted physical vapor deposition (IBAD). Materials undergoing testing demonstrate excellent durability under accelerated and outdoor weathering. To help commercialize the technology, NREL had a cost analysis performed incorporating realistic web coating assumptions and the technical improvements made in the ASRM. The biggest process cost items are the alumina and machine burden (which collects the cost of the building and office staff). The switch from a polyethylene terethaphalate (PET) to a steel substrate for the ASRM is a significant contributor to the cost. The cost of high-purity alumina should drop from $400 to $200/kg when purchased in 20 kg quantities. Alumina deposition rate then becomes the critical cost driver. In a previous study, deposition rates above 100 nm/s were not examined, but deposition rates greater than 100 nm/s are being used routinely for thin alumina coatings deposited on commercial web-coaters as barrier coatings. In addition, multiple (2–3) Al2O3 IBAD zones can be used in one roll-coating machine to deposit thicker alumina at a lower web speed. This means that with increasing deposition rate and/or multiple zones, the total production cost of the SAIC ASRM with 1 μm thick Al2O3 on PET will meet both the 1992 cost goal of $10.76/m2$1/ft2 and the equivalent cost goal of $13.79/m2$1.31/ft2 when the 1992 cost goal is corrected for inflation. There is a minimum deposition rate needed to reach the cost goal and a maximum deposition rate related to the number of zones after which no significant cost gains are observed. These asymptotic total production costs are $8.06/m2($7.39/m2 excluding substrate) for a large commercial web-coating company and $7.62/m2($6.94/m2 excluding substrate) for a smaller company. As can be seen by these numbers, the $10.76/m2 cost goal can be reached, but the cost of the substrate is still a major consideration. In addition, the width of the web was increased from 600 to 1200 mm, which decreased the asymptotic total production costs. The results of the cost analysis will be described.

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