Measurement of Solar Limb Darkening at Hydrogen Alpha

Ajraini Nazli, Nadiya Rahma Ardilla

Abstract


Sun disc has a lower intensity at the limb where it looks darker than at the center. This effect known as solar limb darkening. In this study, we determine the solar limb darkening at hydrogen alpha with 656 nm thus we can compare the result to the previous studies. We have taken the solar images at Observatorium Ilmu Falak Universitas Muhammadiyah Sumatera Utara (OIF UMSU). Limb-darkening coefficient is obtained through least-square fitting with the linear limb-darkening law. The result shows linear limb-darkening coefficient is 0.607 and it gives good agreement with the previous studies. In addition, this study is the initial stage of limb darkening research at OIF UMSU and can be continued with more observational data.

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