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arXiv · 0805.4296

Stokes imaging polarimetry using image restoration at the Swedish 1-m Solar Telescope

M. J. van Noort·L. H. M. Rouppe van der Voort
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Abstract

Aims: We aim to achieve high spatial resolution as well as high polarimetric sensitivity, using an earth-based 1m-class solar telescope, for the study of magnetic fine structure on the Sun. Methods: We use a setup with 3 high-speed, low-noise cameras to construct datasets with interleaved polarimetric states, particularly suitable for Multi-Object Multi-Frame Blind Deconvolution image restorations. We discuss the polarimetric calibration routine as well as various potential sources of error in the results. Results: We obtained near diffraction limited images, with a noise level of approximately 10^(-3) I(cont). We confirm that dark-cores have a weaker magnetic field and at a lower inclination angle with respect to the solar surface than the edges of the penumbral filament. We show that the magnetic field strength in faculae-striations is significantly lower than in other nearby parts of the faculae.

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M. J. van Noort, L. H. M. Rouppe van der Voort. 2008-05-28. Stokes imaging polarimetry using image restoration at the Swedish 1-m Solar Telescope. https://doi.org/10.1051/0004-6361%3A200809959

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