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arXiv · 2505.04239

High polarization lines of the second solar spectrum of the Solar limb

Jean-Marie Malherbe
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Abstract

We present a dataset of high resolution spectra of the Sun of many strongly polarized lines belonging to the second solar spectrum, i.e. the spectrum near the limb in linear polarization (scattering polarization). These solar spectra were obtained in full Stokes polarimetry (I, Q/I, U/I, V/I) in the quiet Sun at various distances from the limb, and at disk centre for comparison, with the ground based CNRS THEMIS telescope. Polarization rates Q/I up to 7% are obtained in CaI 4227 {\AA} line at $\mu$ = cos$\theta$ = 0, while 2% is reached in SrI 4607 {\AA} line and 1.4% in BaII 4554 {\AA}. The spectra shown here are freely available in FITS format to the research community.

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Jean-Marie Malherbe. 2025-05-07. High polarization lines of the second solar spectrum of the Solar limb. https://arxiv.org/abs/2505.04239

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