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Results for “VACUUM ULTRAVIOLET”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

Generation of ultraviolet and vacuum ultraviolet radiation

The paper describes the use of nonlinear optical techniques for the generation of coherent radiation at ultraviolet, vacuum ultraviolet, and soft X-ray wavelengths. Mixtures of metal vapors and inert gases, and other mixed gas systems, allow generation to regions of the spectrum where nonlinear optical crystals are opaque; and also allow generations at high incident power and energy densities. Progress is reported on programs aimed at efficient conversion from 1.064 microns to 3547 A, and from 3547 A to 1182 A. To date, the shortest wavelength generated by this technique is 887 A. Theoretical considerations indicate that generation into the soft X-ray region should be possible. Using 1182 A radiation, a holographic grating with a fringe spacing of 836 A has been constructed and examined on an electron microscope.

Harris, S. E.↗
NASA NTRS1975

Generation of ultraviolet and vacuum ultraviolet radiation

The paper describes nonlinear optical techniques that use phase-matched mixtures of metal vapors and inert gases, or, in certain cases, only inert gases for the generation of ultraviolet radiation. These systems are transparent where nonlinear crystals are opaque and their high ionization permits optical power densities of 10 to the 10 or 10 to the 11 W/sq cm to be utilized. An experiment designed to convert incident 1.064 micron radiation to 3547 A radiation is described as are experiments designed to generate vacuum ultraviolet at 1773, 1520, 1182 and 887 A. Theoretical considerations on the use of this nonlinear optical technique for the generation of soft X-rays are presented and the construction of a vacuum ultraviolet holographic grating with a fringe spacing of 836 A is reported on.

Harris, S. E.↗
NASA NTRS1981

Photon-counting array detectors for space and ground-based studies at ultraviolet and vacuum ultraviolet /VUV/ wavelengths

The Multi-Anode Microchannel Arrays (MAMAs) are a family of photoelectric photon-counting array detectors, with formats as large as (256 x 1024)-pixels that can be operated in a windowless configuration at vacuum ultraviolet (VUV) and soft X-ray wavelengths or in a sealed configuration at ultraviolet and visible wavelengths. This paper describes the construction and modes of operation of (1 x 1024)-pixel and (24 x 1024)-pixel MAMA detector systems that are being built and qualified for use in sounding-rocket spectrometers for solar and stellar observations at wavelengths below 1300 A. The performance characteristics of the MAMA detectors at ultraviolet and VUV wavelengths are also described.

Timothy, J. G.↗
NASA NTRS1992

Radiative lifetimes in B I using ultraviolet and vacuum-ultraviolet laser-induced fluorescence

Radiative lifetimes of the eight lowest even parity levels in the doublet system of B I are measured using time-resolved laser-induced fluorescence in the UV and VUV on an atomic beam of boron. The accurate lifetimes provide a base for improved determination of absolute transition probabilities in B I. The techniques described are broadly applicable to measurement of lifetimes of levels with transitions in the visible, UV, and VUV in almost any element.

O'Brian, T. R.↗
NASA NTRS1990

Vacuum ultraviolet thin films. I - Optical constants of BaF2, CaF2, LaF3, MgF2, Al2O3, HfO2, and SiO2 thin films. II - Vacuum ultraviolet all-dielectric narrowband filters

An iteration process matching calculated and measured reflectance and transmittance values in the 120-230 nm VUV region is presently used to ascertain the optical constants of bulk MgF2, as well as films of BaF2, CaF2, LaF3, MgF2, Al2O3, HfO2, and SiO2 deposited on MgF2 substrates. In the second part of this work, a design concept is demonstrated for two filters, employing rapidly changing extinction coefficients, centered at 135 nm for BaF2 and 141 nm for SiO2. These filters are shown to yield excellent narrowband spectral performance in combination with narrowband reflection filters.

Zukic, Muamer↗