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[en] Solid, unquenched, radiophosphorescent standards for use in the day-to-day calibration of bottom viewing photometers (luminometers) were prepared by encapsulating commercially-available phosphor powders that are excited to phosphoresce by the β- decay of 63Ni (t0.5 = 96 yr) or 14C (t0.5 = 5730 yr). The encapsulated photometer standards have remained mechanically and photometrically stable since their fabrication, which in some cases is 3 years ago. An equivalent level of visible luminescence emitted from the standards of up to 2.3 x 1010 photons.s-1 was achieved by using an appropriate amount of radioactivity and the proper phosphor. The phosphor used in the standards could be chosen such that the radiophosphorescence emission spectrum corresponded approximately to the chemiluminescence or bioluminescence spectrum under investigation. (author)
[en] Complete text of publication follows. The inverse problem to retrieve useful airglow volume emission rate profiles from rocket-borne photometer measurements has been solved by adopting the well-characterized spectral photometric methods. An alternative recovery method based on artificial neural network (ANN) is presented. In this work, a multilayer perceptron neural network was trained with a range of cases from the empirical and experimental volume emission rate profiles. A numerical experiment was also carried out with synthetic experimental data considering a noise level of 5%. Integrated emission profiles measured by a Brazilian sounding rocket experiment launched from an Equatorial station were taken as the input data. From the results obtained it may be concluded that the ANN technique is a convenient tool to recover volume emission rate profiles. The advantages of using neural network based systems are related to their intrinsic features of parallelism, after trained, the networks are much faster than traditional inversion approaches.
[en] Measurements of the contrast at 525 nm of solar faculae are presented. These measurements were obtained with an extreme limb photometer (ELP) in 19775 and 1979 at the San Fernando Observatory. The mean contrast of active regions was determined from the limb inward to 54'', averaged over an annulus determined by the slits of the ELP. We find that the contrast of faculae increases with heliocentric angle theta, from μroughly-equal0.25 to μroughly-equal0.065, where μ = cos theta. The average value of the mean contrast of facular regions is 2.1% with a possible upper limit of about 5% at μroughly-equal0.1, determined from regions with the greatest filling factor. This mean contrast, when corrected for a filling factor of 10-15% implies a contrast for individual faculae of 30-50%. The results from the two observing seasons, when combined, are not inconsistent with the μ-dependence of the excess solar oblateness signal measured at Princeton in 1966. The 1979 facular data would have produced an apparent excess oblateness of 66% of the Dicke and Goldenberg value. Because the contrast of faculae appears to increase to within a few arcsec of the limb, the excess facular intensity is probably due not only to ''hot wall'' effects but also to local heating in the upper levels of facular flux tubes
[en] An instrument was designed for measuring sodium aerosols concentrations using flame photometry. The instrument meets the requirements for long-term measurement. Sodium particles are heated in a hydrogen flame to the temperature required for excitation and they emit the characteristic yellow coloured flame. The hydrogen flame light containing sodium particles does not pass through a monochromatic spectral filter for the sodium spectral line to the pohotomultiplier cathode whose current is proportional to the intensity of the impacting light. The electronic part of the instrument consisting of replaceable modules is built using units available on the home market. (Kr)