Bibcode
Campbell, Ryan J.; Quintero Noda, Carlos; Mathioudakis, Mihalis; Collados, Manuel; McFall, Jack; Jess, David B.; Solanki, Sami K.; Lagg, Andreas; Gandorfer, Achim; del Toro Iniesta, Jose Carlos; Katsukawa, Yukio; Bernasconi, Pietro; Berkefeld, Thomas; Feller, Alex; Riethmüller, Tino L.; Álvarez-Herrero, Alberto; Kubo, Masahito; Smitha, H. N.; Orozco Suárez, David; Grauf, Bianca; Carpenter, Michael; Bell, Alexander; Martínez Pillet, Valentín; Bailén, Francisco Javier; Blanco Rodríguez, Julian; Castellanos Durán, Juan Sebastián; Harnes, Edvarda; Hölken, Johannes; Iglesias, Francisco A.; Ishikawa, Ryohtaroh T.; Kawabata, Yusuke; Matsumoto, Takuma; Oba, Takayoshi; Siu-Tapia, Azaymi L.; Strecker, Hanna; Vukadinović, Dušan; Hara, Hirohisa; Shimizu, Toshifumi
Bibliographical reference
The Astrophysical Journal Letters
Advertised on:
9
2026
Citations
1
Refereed citations
0
Description
We present high-resolution multiline spectropolarimetric observations of a quiet-Sun network element obtained with the SUNRISE III Chromospheric Infrared SpectroPolarimeter. The observations combine photospheric, upper-photospheric, and chromospheric diagnostics at a spatial resolution and polarimetric sensitivity that allow the transverse magnetic structure of the network boundary to be examined directly. We find that the strongest linear polarization is concentrated in a narrow ridge around the edge of the magnetic element, cospatial with enhanced transverse magnetic field inferred from multiline inversions. The magnetic azimuth exhibits a coherent, predominantly radial organization around a more vertical core, consistent with an expanding magnetic canopy. An azimuth proxy derived directly from the observed Fe I and K I linear polarization reproduces the same large-scale organization, showing that this structure is encoded in the Stokes profiles rather than imposed by the inversion. Response functions and a MURaM-based forward-synthesis test indicate that the Fe I 8468 Å linear polarization is sensitive to magnetic azimuth in the upper photosphere, with the closest proxy agreement occurring near logτ≈-3 . We find no evidence for strong azimuthal shear between the Fe- and K-sensitive diagnostics. At the network boundary, we also identify localized parasitic-polarity patches associated with complex, multilobed Stokes V profiles and one case in which the Stokes V polarity reverses between photospheric Fe I and chromospheric Ca II lines. These results demonstrate that quiet-Sun network boundaries contain organized upper-photospheric canopy fields together with a small-scale mixed-polarity structure, providing new constraints on the three-dimensional magnetic structure of network elements.