Origin of small-scale evaporation flows deep in the chromosphere during a solar flare
Abstract
Flares are caused by an abrupt release of magnetic energy in the solar atmosphere. Plasma heated to well over 10 MK filling the post-flare corona originates from a rapid heating and ablation of the cooler chromospheric material. This chromospheric evaporation is thought to be facilitated primarily by nonthermal electrons impinging on to the lower atmosphere. Questions on when and where in the chromosphere these upflows originate, however, are not fully resolved. Here we report on unprecedented high-resolution observations of an M-class flare recorded by the Sunrise Ultraviolet Spectropolarimeter and Imager on board the balloon-borne SUNRISE observatory, that reveal highly structured upflows on spatial scales of ~100 km originating deep in the chromosphere. The flows even precede the onset of nonthermal electrons by about 10 minutes and last through the impulsive phase of the flare. Our observations shed new light on the lower atmospheric heating and mass circulation in flares that are challenging to reconcile with the standard solar flare model.
Versions
Related
- Chromosphere of the quiet Sun: II. Atmospheric response to small-scale magnetic flux emergence
- H β Spicules, Small-scale Jets, and H β Microflashes: Subarcsecond Dynamic Events and Their Magnetic Origins in the Lower Solar Chromosphere Observed by DKIST
- Hbeta Spicules, Small-scale Jets, and Hbeta Microflashes: Sub-arcsecond Dynamic Events and their Magnetic Origins in the Lower Solar Chromosphere Observed by DKIST
- Audible curvaton: modulated phase transition as the origin of large-scale curvature perturbations and gravitational wave anisotropies
- Analysis of a coronal hole jet in the chromosphere and the transition region with IRIS and SDO observations
BibTeX
@misc{chitta2026origin,
title = {{Origin of small-scale evaporation flows deep in the chromosphere during a solar flare}},
author = {L. P. Chitta and H. N. Smitha and F. A. Iglesias and T. L. Riethmüller and A. Feller and W. Chen and A. Lagg and A. Gandorfer and J. Hölken and S. K. Solanki and J. C. del Toro Iniesta and Y. Katsukawa and P. Bernasconi and T. Berkefeld and A. Álvarez-Herrero and M. Kubo and D. Orozco Suárez and B. Grauf and M. Carpenter and A. Bell and Valentín Martínez Pillet and F. J. Bailén and J. Blanco Rodríguez and J. Sebastián Castellanos Durán and E. Harnes and R. T. Ishikawa and Y. Kawabata and T. Matsumoto and T. Oba and A. L. Siu-Tapia and H. Strecker and D. Vukadinović},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2608.29649},
eprint = {2608.29649},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2608.29649},
}
RIS
TY - UNPB
TI - Origin of small-scale evaporation flows deep in the chromosphere during a solar flare
AU - L. P. Chitta
AU - H. N. Smitha
AU - F. A. Iglesias
AU - T. L. Riethmüller
AU - A. Feller
AU - W. Chen
AU - A. Lagg
AU - A. Gandorfer
AU - J. Hölken
AU - S. K. Solanki
AU - J. C. del Toro Iniesta
AU - Y. Katsukawa
AU - P. Bernasconi
AU - T. Berkefeld
AU - A. Álvarez-Herrero
AU - M. Kubo
AU - D. Orozco Suárez
AU - B. Grauf
AU - M. Carpenter
AU - A. Bell
AU - Valentín Martínez Pillet
AU - F. J. Bailén
AU - J. Blanco Rodríguez
AU - J. Sebastián Castellanos Durán
AU - E. Harnes
AU - R. T. Ishikawa
AU - Y. Kawabata
AU - T. Matsumoto
AU - T. Oba
AU - A. L. Siu-Tapia
AU - H. Strecker
AU - D. Vukadinović
PY - 2026
DA - 2026/09/11
PB - arXiv
DO - 10.48550/arxiv.2608.29649
UR - https://arxiv.org/abs/2608.29649
AB - Flares are caused by an abrupt release of magnetic energy in the solar atmosphere. Plasma heated to well over 10 MK filling the post-flare corona originates from a rapid heating and ablation of the cooler chromospheric material. This chromospheric evaporation is thought to be facilitated primarily by nonthermal electrons impinging on to the lower atmosphere. Questions on when and where in the chromosphere these upflows originate, however, are not fully resolved. Here we report on unprecedented high-resolution observations of an M-class flare recorded by the Sunrise Ultraviolet Spectropolarimeter and Imager on board the balloon-borne SUNRISE observatory, that reveal highly structured upflows on spatial scales of ~100 km originating deep in the chromosphere. The flows even precede the onset of nonthermal electrons by about 10 minutes and last through the impulsive phase of the flare. Our observations shed new light on the lower atmospheric heating and mass circulation in flares that are challenging to reconcile with the standard solar flare model.
ER -