Sunrise III/SUSI reveals extended and spectrally structured Ca II K emission above the solar limb

@misc{milic2026sunrise,
  title = {{Sunrise III/SUSI reveals extended and spectrally structured Ca II K emission above the solar limb}},
  author = {Ivan Milić and Christopher M. J. Osborne and Francisco A. Iglesias and Juan Sebastián Castellanos Durán and Damien F. Przybylski and Lakshmi Pradeep Chitta and Sanghita Chandra and Andreas Lagg and Sami K. Solanki and Tino L. Riethmüller and Achim Gandorfer and Alex Feller and Johannes Hoelken and H. N. Smitha and Jose Carlos del Toro Iniesta and Yukio Katsukawa and Pietro Bernasconi and Thomas Berkefeld and Alberto Álvarez-Herrero and Masahito Kubo and Valentín Martínez Pillet and David Orozco Suárez and Bianca Grauf and Michael Carpenter and Alexander Bell and Hanna Strecker and Azaymi L. Siu-Tapia and Pablo Santamarina Guerrero and Julian Blanco Rodríguez and Yusuke Kawabata and Takuma Matsumoto and Ryohtaroh T. Ishikawa and Edvarda Harnes and Takayoshi Oba and Dušan Vukadinović},
  howpublished = {arXiv},
  year = {2026},
  month = sep,
  doi = {10.48550/arxiv.2609.38575},
  eprint = {2609.38575},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2609.38575},
  note = {CC BY 4.0},
}

TY  - UNPB
TI  - Sunrise III/SUSI reveals extended and spectrally structured Ca II K emission above the solar limb
AU  - Ivan Milić
AU  - Christopher M. J. Osborne
AU  - Francisco A. Iglesias
AU  - Juan Sebastián Castellanos Durán
AU  - Damien F. Przybylski
AU  - Lakshmi Pradeep Chitta
AU  - Sanghita Chandra
AU  - Andreas Lagg
AU  - Sami K. Solanki
AU  - Tino L. Riethmüller
AU  - Achim Gandorfer
AU  - Alex Feller
AU  - Johannes Hoelken
AU  - H. N. Smitha
AU  - Jose Carlos del Toro Iniesta
AU  - Yukio Katsukawa
AU  - Pietro Bernasconi
AU  - Thomas Berkefeld
AU  - Alberto Álvarez-Herrero
AU  - Masahito Kubo
AU  - Valentín Martínez Pillet
AU  - David Orozco Suárez
AU  - Bianca Grauf
AU  - Michael Carpenter
AU  - Alexander Bell
AU  - Hanna Strecker
AU  - Azaymi L. Siu-Tapia
AU  - Pablo Santamarina Guerrero
AU  - Julian Blanco Rodríguez
AU  - Yusuke Kawabata
AU  - Takuma Matsumoto
AU  - Ryohtaroh T. Ishikawa
AU  - Edvarda Harnes
AU  - Takayoshi Oba
AU  - Dušan Vukadinović
PY  - 2026
DA  - 2026/09/29
PB  - arXiv
DO  - 10.48550/arxiv.2609.38575
UR  - https://arxiv.org/abs/2609.38575
AB  - The Sunrise III/SUSI instrument performed a sit-and-stare observation of the off-limb emission in the Ca II K line core, with a combination of excellent temporal and spectral resolution. The emission reaches up to 6 Mm above the solar limb, indicating the existence of off-limb structures akin to spicules. In this letter, we describe the spatio-spectral properties of the observed emission, focusing on the spectral line shape resolved in detail by Sunrise III/SUSI, and compare the observation with simple modeling that relies on a numerical simulation of the solar chromosphere. We find that the simulation contains enough cool and dense material at Mm heights to produce off-limb emission, but that the spectral width of these features is slightly lower than observed, necessitating more detailed modeling.
ER  -