摘要 :
Two experimental setups have been used in this work on the effects of vacuum ultraviolet light on surface breakdown. The first experimental setup was designed so that VUV emission from an excited surface flashover event is focused...
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Two experimental setups have been used in this work on the effects of vacuum ultraviolet light on surface breakdown. The first experimental setup was designed so that VUV emission from an excited surface flashover event is focused onto the entrance slit of a vacuum spectrograph, with the spark simultaneously being imaged by a fast shutter ICCD on the atmospheric side. The dielectric surface was an MgF2 window and an MgF2 lens was used to focus the light on the spectrometer entrance slit. The second experimental setup used mirrors in place of the MgF2 lens thus increasing the light below 130 nm entering the spectrometer.
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摘要 :
A classic double ribbon flare of importance 1B occurred at approximately 1405 UT on June 15, 1973, reached an H alpha maximum at 1413 UT, and ended at 1455 UT. The flare occurred in an old and simplifying bipolar region at N18 W32...
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A classic double ribbon flare of importance 1B occurred at approximately 1405 UT on June 15, 1973, reached an H alpha maximum at 1413 UT, and ended at 1455 UT. The flare occurred in an old and simplifying bipolar region at N18 W32. This flare was studied due to the extensive temporal data available. A total of 136 spectra of wavelength ranges from 1100 to 3000 A were taken during the flare's duration by the Naval Research Laboratory normal incidence slit spectrograph. Using this data the nature of the solar chromosphere of a flare event as a function of time was determined.
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摘要 :
A low-pressure hydrogen discharge lamp has been calibrated for radiant intensity in the vacuum ultraviolet spectral region on an absolute basis and has been employed as a laboratory standard source in spectrograph calibrations. Th...
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A low-pressure hydrogen discharge lamp has been calibrated for radiant intensity in the vacuum ultraviolet spectral region on an absolute basis and has been employed as a laboratory standard source in spectrograph calibrations. This calibration was accomplished through the use of a standard photodiode detector obtained from the National Bureau of Standards together with onsite measurements of spectral properties of optical components used. The stability of the light source for use in the calibration of vacuum ultraviolet spectrographs and optical systems has been investigated and found to be amenable to laboratory applica¬tions. The lamp was studied for a range of operating parameters; the results indicate that with appropriate peripheral instrumentation, the light source can be used as a secondary laboratory standard source when operated under preset controlled conditions. Absolute intensity measurements were recorded for the wavelengths 127.7, 158.0, 177.5, and 195.0 nm for a time period of over 1 month, and the measurements were found to be repeatable to within 11 percent.
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