Hidden magnetic fields of the quiet Sun derived from Hanle depolarization of lines of the “second solar spectrum” at the limb from Pic du Midi observations

DOI

This dataset contains many strongly polarized solar lines belonging to the “second solar spectrum”, i.e. the spectrum near the limb in linear scattering polarization. The observations were done at the Pic du Midi Turret Dome in 2006. The solar spectra were recorded at high spectral resolution (R = 400000) with the spectrograph slit orthogonal to the solar limb, so that µ = cosθ continuously varied from 0.0 to 0.45. The crystal liquid polarimeter delivered the linear polarization rate (Q/I). Strong lines such as CaII 3934 Å, CaI 4227 Å, SrI 4607 Å, SrII 4078 Å, BaII 4554 Å were studied. We measured the Hanle depolarization with the help of models predicting the polarization envelope with no magnetic field and we got values in the range 13-25 Gauss for the unresolved turbulent magnetic field, and we found that it often decreases towards the limb, revealing an altitude gradient. The processed spectra of this dataset are available to the research community.

Identifier
DOI https://doi.org/10.57745/RQ1USZ
Related Identifier IsCitedBy https://doi.org/10.1051/0004-6361:20065910
Metadata Access https://entrepot.recherche.data.gouv.fr/oai?verb=GetRecord&metadataPrefix=oai_datacite&identifier=doi:10.57745/RQ1USZ
Provenance
Creator Malherbe, Jean-Marie ORCID logo
Publisher Recherche Data Gouv
Contributor Malherbe, Jean-Marie
Publication Year 2025
Rights etalab 2.0; info:eu-repo/semantics/openAccess; https://spdx.org/licenses/etalab-2.0.html
OpenAccess true
Contact Malherbe, Jean-Marie (Observatoire de Paris - PSL)
Representation
Resource Type Dataset
Format application/zip
Size 20536192
Version 1.0
Discipline Astrophysics and Astronomy; ['Sun']; ['Strontium']; ['Barium']; ['Calcium']; ['Hanle depolarization']; ['Magnetic field']; ['Spectra']; ['Polarization']