Measuring the Expansion of Solar Magnetic Fields with Multiline Inversions from Sunrise III

@misc{arjona2026measuring,
  title = {{Measuring the Expansion of Solar Magnetic Fields with Multiline Inversions from Sunrise III}},
  author = {Juan Carlos Trelles Arjona and María Jesús Martínez González and Christoph Kuckein and Sergio Javier González Manrique and Manuel Collados and Sami K. Solanki and Andreas Lagg and Achim Gandorfer and Jose Carlos del Toro Iniesta and Yukio Katsukawa and Pietro Bernasconi and Thomas Berkefeld and Alex Feller and Tino L. Riethmüller and Alberto Álvarez-Herrero and Masahito Kubo and H. N. Smitha and David Orozco Suárez and Bianca Grauf and Michael Carpenter and Alexander Bell and Valentín Martínez Pillet and Francisco Javier Bailén and Julian Blanco Rodríguez and Juan Sebastián Castellanos Durán and Edvarda Harnes and Johannes Hölken and Francisco A. Iglesias and Ryohtaroh T. Ishikawa and Yusuke Kawabata and Takuma Matsumoto and Takayoshi Oba and Azaymi L. Siu-Tapia and Hanna Strecker and Dušan Vukadinović and Hirohisa Hara and Toshifumi Shimizu},
  howpublished = {arXiv},
  year = {2026},
  month = sep,
  doi = {10.48550/arxiv.2609.31822},
  eprint = {2609.31822},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2609.31822},
  note = {CC BY 4.0},
}

TY  - UNPB
TI  - Measuring the Expansion of Solar Magnetic Fields with Multiline Inversions from Sunrise III
AU  - Juan Carlos Trelles Arjona
AU  - María Jesús Martínez González
AU  - Christoph Kuckein
AU  - Sergio Javier González Manrique
AU  - Manuel Collados
AU  - Sami K. Solanki
AU  - Andreas Lagg
AU  - Achim Gandorfer
AU  - Jose Carlos del Toro Iniesta
AU  - Yukio Katsukawa
AU  - Pietro Bernasconi
AU  - Thomas Berkefeld
AU  - Alex Feller
AU  - Tino L. Riethmüller
AU  - Alberto Álvarez-Herrero
AU  - Masahito Kubo
AU  - H. N. Smitha
AU  - David Orozco Suárez
AU  - Bianca Grauf
AU  - Michael Carpenter
AU  - Alexander Bell
AU  - Valentín Martínez Pillet
AU  - Francisco Javier Bailén
AU  - Julian Blanco Rodríguez
AU  - Juan Sebastián Castellanos Durán
AU  - Edvarda Harnes
AU  - Johannes Hölken
AU  - Francisco A. Iglesias
AU  - Ryohtaroh T. Ishikawa
AU  - Yusuke Kawabata
AU  - Takuma Matsumoto
AU  - Takayoshi Oba
AU  - Azaymi L. Siu-Tapia
AU  - Hanna Strecker
AU  - Dušan Vukadinović
AU  - Hirohisa Hara
AU  - Toshifumi Shimizu
PY  - 2026
DA  - 2026/09/25
PB  - arXiv
DO  - 10.48550/arxiv.2609.31822
UR  - https://arxiv.org/abs/2609.31822
AB  - Magnetic fields in the solar atmosphere are expected to expand with height, forming magnetic canopies that couple the photosphere and chromosphere. Except for sunspots, direct measurements of this expansion remain scarce because they require simultaneous magnetic diagnostics over a broad range of atmospheric heights. We analyze four consecutive high-resolution spectropolarimetric raster scans of an emerging flux region observed with the Sunrise III/SCIP instrument. Simultaneous inversions of five photospheric Fe I lines and two chromospheric Ca II lines provide a quasi-continuous reconstruction of the magnetic field from the deep photosphere to the lower chromosphere. We apply a constant-flux method that follows the same magnetic flux through different atmospheric layers to quantify magnetic expansion. All three pores analyzed exhibit an overall increase in magnetic area with height, approximately doubling their cross section between the lower photosphere and the highest atmospheric layers sampled by the inversions. The expansion remains broadly stable throughout the 48-minute observing sequence. We further characterize the expansion with a quadratic parameterization and investigate its relation to pore properties. The three pores exhibit similar core magnetic field strengths but different expansion behaviors, indicating that the magnetic core strength alone does not determine the expansion. However, the present sample is too small to establish whether these differences are related to the thermodynamic or magnetic properties of the pores and their surroundings. These results demonstrate the potential of simultaneous multiline inversions for investigating the three dimensional magnetic topology of solar magnetic structures and provide the first direct measurements of the height-dependent magnetic expansion of solar pores.
ER  -