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arXiv · 2608.00619

Three-dimensional Magnetic Structures of Ellerman Bombs revealed by SUNRISE III/SCIP

Yusuke Kawabata·Yukio Katsukawa·Masahito Kubo·Takayoshi Oba·Takuma Matsumoto·Ryohtaroh T. Ishikawa·Yoshihiro Naito·Hirohisa Hara·Toshifumi Shimizu·Fumihiro Uraguchi·Toshihiro Tsuzuki·Kazuya Shinoda·Tomonori Tamura·Yoshinori Suematsu·Carlos Quintero Noda·Jose Carlos del Toro Iniesta·David Orozco Suárez·María Balaguer Jimenez·Sami K. Solanki·Andreas Lagg·Achim Gandorfer·Pietro Bernasconi·Thomas Berkefeld·Alex Feller·Tino L. Riethmüller·Alberto Álvarez-Herrero·H. N. Smitha·Bianca Grauf·Michael Carpenter·Alexander Bell·Valentín Martínez Pillet·Francisco Javier Bailén·Julian Blanco Rodríguez·Juan Sebastián Castellanos Durán·Edvarda Harnes·Johannes Hoelken·Francisco A. Iglesias·Azaymi L. Siu-Tapia·Hanna Strecker·Dušan Vukadinović
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Abstract

Ellerman bombs (EBs) are widely recognized as photospheric and chromospheric signatures of magnetic reconnection. However, the three-dimensional (3D) magnetic topology has remained elusive due to the lack of seamless height coverage in observations. Here, we present initial results from the SUNRISE III/SCIP (Sunrise Chromospheric Infrared spectroPolarimeter) observations of an emerging flux region. Exploiting the seeing-free, high-spatial-resolution observations provided by the 1-meter balloon-borne telescope, SCIP achieved seamless multi-line spectropolarimetry from the photosphere to the lower chromosphere. We analyzed the multi-line Stokes profiles of the photospheric Fe I and K I lines and the chromospheric Ca II lines, and applied the Weak Field Approximation to the K I and Ca II lines to reconstruct the 3D magnetic field structure. The blue- and red-wing brightenings of the Ca II 8542 {\AA} line appear at spatially offset locations, indicating bi-directional reconnection flows. The reconstructed 3D magnetic field reveals that the opposite-polarity field structure reaches different heights in the two events analyzed. In one event, it is confined to the lower layers and is absent at the formation height of Ca II 8542 {\AA} core, which shows no intensity enhancement, whereas in the other event it extends up to the Ca II 8542 {\AA} core formation height, where enhanced line-core intensity is also observed. We interpret this as the reconnection current sheet reaching different altitudes. These results demonstrate that SCIP has successfully resolved the 3D structure of EBs, distinguishing magnetic reconnection events occurring at different atmospheric heights.

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Yusuke Kawabata, Yukio Katsukawa, Masahito Kubo, Takayoshi Oba, Takuma Matsumoto, Ryohtaroh T. Ishikawa, Yoshihiro Naito, Hirohisa Hara, Toshifumi Shimizu, Fumihiro Uraguchi, Toshihiro Tsuzuki, Kazuya Shinoda, Tomonori Tamura, Yoshinori Suematsu, Carlos Quintero Noda, Jose Carlos del Toro Iniesta, David Orozco Suárez, María Balaguer Jimenez, Sami K. Solanki, Andreas Lagg, Achim Gandorfer, Pietro Bernasconi, Thomas Berkefeld, Alex Feller, Tino L. Riethmüller, Alberto Álvarez-Herrero, H. N. Smitha, Bianca Grauf, Michael Carpenter, Alexander Bell, Valentín Martínez Pillet, Francisco Javier Bailén, Julian Blanco Rodríguez, Juan Sebastián Castellanos Durán, Edvarda Harnes, Johannes Hoelken, Francisco A. Iglesias, Azaymi L. Siu-Tapia, Hanna Strecker, Dušan Vukadinović. 2026-08-01. Three-dimensional Magnetic Structures of Ellerman Bombs revealed by SUNRISE III/SCIP. https://doi.org/10.3847/2041-8213%2Fae91e0

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