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arXiv · 2207.07728

A Compact Full-disk Solar Magnetograph based on miniaturization of GONG instrument

Sanjay Gosain·Jack Harvey·Valentin Martinez-Pillet·Tom Woods·Frank Hill
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Abstract

Designing compact instruments is the key for the scientific exploration by smaller spacecrafts such as cubesats or by deep space missions. Such missions require compact instrument designs to have minimal instrument mass. Here we present a proof of concept for miniaturization of the Global Oscillation Network Group GONG instrument. GONG instrument routinely obtains solar full disk Doppler and magnetic field maps of the solar photosphere using Ni 676 nm absorption line. A key concept for miniaturization of GONG optical design is to replace the bulky Lyot filter with a narrow-band interference filter and reduce the length of feed telescope. We present validation of the concept via numerical modeling as well as by proof of concept observations.

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Sanjay Gosain, Jack Harvey, Valentin Martinez-Pillet, Tom Woods, Frank Hill. 2022-07-15. A Compact Full-disk Solar Magnetograph based on miniaturization of GONG instrument. https://doi.org/10.1088/1538-3873%2Facca49

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