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arXiv · 1106.2197

Towards a unified definition of solar limb during central eclipses and daily transits

Costantino Sigismondi·Andrea Raponi·Cyril Bazin·Richard Nugent
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Abstract

The diameter of the Sun has been measured using Baily's beads during central eclipses, observed with portable telescopes. A blend of tiny emission lines produced in the first several hundred kilometers above the photosphere gives a light signal which prolonges the light curves of the beads. The simple criterion of light OFF/ON adopted in the previous approaches to define the timing of photosphere's disappearance/reappearance is modified. The technique of the limb darkening function reconstruction from the Baily's beads light curves is introduced here.

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Costantino Sigismondi, Andrea Raponi, Cyril Bazin, Richard Nugent. 2011-06-11. Towards a unified definition of solar limb during central eclipses and daily transits. https://doi.org/10.1016/j.jare.2012.12.003

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