All-sky imager radiometric calibration method based on fixed star radiation spectrum and flux

Abstract

The embodiment of the invention discloses an all-sky imager radiation calibration method based on a fixed star radiation spectrum and flux. The radiometric calibration method comprises the steps of selecting a target fixed star in an all-sky image, determining a zenith angle corresponding to the target fixed star at the moment of the all-sky image at an aurora observation station, and acquiring atmospheric transmissivity at the zenith angle corresponding to the target fixed star on an aurora observation spectral line according to the zenith angle; calculating to obtain photon radiation flux of the target fixed star on the aurora observation spectral line and a first solid angle corresponding to the target fixed star, and determining fixed star radiation brightness of the target fixed star according to the photon radiation flux and the first solid angle; and determining a detector output signal value corresponding to the target fixed star, and determining the radiation coefficient of the all-sky imager according to the detector output signal value, the atmospheric transmissivity and the fixed star radiation brightness. According to the technical scheme of the embodiment of the invention, radiometric calibration can be quickly and accurately carried out on the all-sky imager without geographical limitation, and the radiometric calibration of the all-sky imager is more flexible.

Description

technical field [0001] Embodiments of the present invention relate to the technical field of radiation calibration, and in particular to a radiation calibration method for an all-sky imager based on stellar radiation spectrum and flux. Background technique [0002] The all-sky imager is an important ground-based space environment optical observation equipment. Calibrating the radiation parameters of the all-sky imager can obtain the real excitation intensity of the auroral structure in different observation spectral lines in the all-sky image. The premise of the auroral excitation intensity in the observation equipment data is also the basis for quantitative research on related physical processes and mechanisms. [0003] Before the all-sky imager leaves the factory, the radiation parameters of the "radiation intensity-image value" of the all-sky imager are calibrated mainly through laboratory calibration experiments. During the long-term use of the all-sky imager, due to Th...

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Problems solved by technology

At present, the radiation calibration of the all-sky imager is carried out in the optical laboratory, and the calibration sources used are artificial radiation sources such as integrating spheres, tungsten lamps, and Lambertian planes. As far as the all-sky auroral imager in the region) is concerned, it is very difficult to recalibrate in the laboratory due to the limitation of the site conditions

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