Journal ArticleDOI
Solar magnetograph employing integrated diode arrays.
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TLDR
Operated at near liquid nitrogen temperature, the noise and cooling characteristics indicate the detector has promise as a low light level sensor beyond the needs of the magnetograph.Abstract:
A solar magnetograph employing as detectors a pair of self-scanning 512-element integrated diode arrays is described. Coupled to a 1.5-m telescope, photospheric flux as small as 5(106) maxwells is detected, corresponding in intensity to ΔI/I = 3(10−4) at λ0.8688 μm. Measured photometric properties of the diode array are given, including MTF as a function of wavelength, dark current as a function of temperature, completeness of readout, optical and electronic fixed-pattern noise. An integrating preamplifier is presented that achieves a measured noise, when connected to the array, equivalent to 950 electrons at the input for a bandwidth of 3(105) Hz. These data provide a basis for an evaluation of the detector performance at low light levels beyond the needs of the magnetograph. Operated at near liquid nitrogen temperature, the noise and cooling characteristics indicate the detector has promise as a low light level sensor.read more
Citations
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Coexistence of ferromagnetism and metallic conductivity in a molecule-based layered compound
Eugenio Coronado,José Ramón Galán-Mascarós,José Ramón Galán-Mascarós,Carlos J. Gómez-García,Vladimir Laukhin,Vladimir Laukhin +5 more
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References
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Journal ArticleDOI
Kitt Peak 60-cm vacuum telescope
TL;DR: Test data in the form of the system MTF and optical transmission, together with examples of full disk magnetograms and photoheliograms, show present performance capability.
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W. C. Livingston,J. Harvey +1 more