Results 121 to 130 of about 1,141 (166)
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Journal of the Optical Society of America, 1959
High sensitivity to auroral Hα, resolution in elevation angle along a narrow band from horizon to horizon, and simplicity of components are principal features of a new automatic auroral spectrograph. Sky light reaches an all-sky convex mirror by way of an external curved slot in the vertical plane, whose calculated shape gives a flat image of uniform ...
K. C. Clark, G. J. Romick
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High sensitivity to auroral Hα, resolution in elevation angle along a narrow band from horizon to horizon, and simplicity of components are principal features of a new automatic auroral spectrograph. Sky light reaches an all-sky convex mirror by way of an external curved slot in the vertical plane, whose calculated shape gives a flat image of uniform ...
K. C. Clark, G. J. Romick
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Optimizing CCDs for spectrographs
Experimental Astronomy, 2000For a spectrograph giving a fixed format spectrum, the quantum efficiency can be optimised for the different wavelengths across the CCD. It is shown that a slight modification of the conventional single layer anti-reflection coating can give major improvements in QE for such instruments, while at the same time minimising problems with fringing and ...
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The Journal of the Acoustical Society of America, 1946
The sound spectrograph is a wave analyzer which produces a permanent visual record showing the distribution of energy in both frequency and time. This paper describes the operation of this device, and shows the mechanical arrangements and the electrical circuits in a particular model.
W. Koenig, H. K. Dunn, L. Y. Lacy
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The sound spectrograph is a wave analyzer which produces a permanent visual record showing the distribution of energy in both frequency and time. This paper describes the operation of this device, and shows the mechanical arrangements and the electrical circuits in a particular model.
W. Koenig, H. K. Dunn, L. Y. Lacy
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The Purification of Spectrographic Carbons
Science, 1941R, Zietlow, P, Hamm, R C, Nelson
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