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arXiv · 2606.11848

Some polarized lines of the second solar spectrum (SrI, CaI, BaII, C2, MgH, NdII) observed at the Meudon Solar Tower spectropolarimeter

Jean-Marie Malherbe
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Abstract

The second solar spectrum is the spectrum of the Stokes parameter Q (linear polarization) close to the solar limb. It is made of a few polarized lines with Q/I of about 1% (such as CaI, SrI, or BaII), but most lines exhibit weaker polarization. This paper presents processing of unpublished observations made in 2008 with the Meudon solar tower spectropolarimeter, which are of interest for weak and turbulent unresolved magnetic field measurements in the quiet Sun, through the Hanle effect.

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Jean-Marie Malherbe. 2026-06-10. Some polarized lines of the second solar spectrum (SrI, CaI, BaII, C2, MgH, NdII) observed at the Meudon Solar Tower spectropolarimeter. https://arxiv.org/abs/2606.11848

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