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The formation of G-band bright points. I: Standard LTE modelling

D. Kiselman·R. J. Rutten·B. Plez
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Abstract

Assuming LTE, we synthesise solar G band spectra from the semiempirical flux-tube model of Briand Solanki (1995). The results agree with observed G-band bright-point contrasts within the uncertainty set by the amount of scattered light. We find that it is the weakening of spectral lines within the flux tube that makes the bright-point contrast in the G band exceed the continuum contrast. We also synthesise flux-tube spectra assuming LTE for the full wavelength range from UV to IR, and identify other promising passbands for flux-tube observations.

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D. Kiselman, R. J. Rutten, B. Plez. 2000-10-19. The formation of G-band bright points. I: Standard LTE modelling. https://arxiv.org/abs/astro-ph/0010390

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