Assessing the impact of background subtraction on a dust-free corona
Abstract
Context. White-light observations of the solar corona contain contributions from both the electron-scattered K-corona and the dust-scattered F-corona. Because the diffuse F-corona dominates the measured intensity at altitudes of approximately 4 R⊙ and above, background subtraction techniques are routinely employed to isolate the electron corona in coronagraph observations. Aims. Since no direct observational "ground truth" for the K-corona exists, the amount of coronal signal that is inadvertently removed by background subtraction methods remains unknown. We aim to quantify, for the first time, the impact of background subtraction on the inferred large-scale structure and brightness of the solar corona. Methods. We use a 32-day simulation based on a novel near-real-time, data-assimilative, time-evolving magnetohydrodynamic model to generate synthetic white-light observables. Because these synthetic observations are free from dust and instrumental stray-light contributions, they provide direct access to the "true" K-corona and enable a quantitative assessment of the effects of background subtraction. Results. We find that background subtraction generally preserves the large-scale morphology of the electron corona, including the locations and shapes of major coronal structures. However, the procedure systematically modifies the relative brightness of different features and removes a non-negligible fraction of the K-coronal signal. Conclusions. Although standard background subtraction techniques successfully recover the overall appearance of the electron corona, they can alter its quantitative photometric properties. These findings should be considered when interpreting coronal brightness measurements and deriving physical properties from processed white-light observations.
Versions
Related
- Untangling dust emission and cosmic infrared background anisotropies with the scattering transform statistics
- The colors of protoplanetary disks. Impact of nonspherical dust particles on the polarized and total intensity colors
- Diffuse Galactic Backgrounds with SPHEREx: A Pilot Study of Background Modeling and Its Impact on Extinction
- Molecular hydrogen formation on dust: The impact of gas-dust drift on formation efficiency
- The impact of feedback and cosmology on Cosmic Infrared Background cross-correlations
BibTeX
@misc{palmerio2026assessing,
title = {{Assessing the impact of background subtraction on a dust-free corona}},
author = {Erika Palmerio and Cooper Downs and Phillip Hess and Benjamin J. Lynch and Ryder Davidson and Ronald M. Caplan and Jon A. Linker},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.15895},
eprint = {2610.15895},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.15895},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Assessing the impact of background subtraction on a dust-free corona
AU - Erika Palmerio
AU - Cooper Downs
AU - Phillip Hess
AU - Benjamin J. Lynch
AU - Ryder Davidson
AU - Ronald M. Caplan
AU - Jon A. Linker
PY - 2026
DA - 2026/10/11
PB - arXiv
DO - 10.48550/arxiv.2610.15895
UR - https://arxiv.org/abs/2610.15895
AB - Context. White-light observations of the solar corona contain contributions from both the electron-scattered K-corona and the dust-scattered F-corona. Because the diffuse F-corona dominates the measured intensity at altitudes of approximately 4 R_⊙ and above, background subtraction techniques are routinely employed to isolate the electron corona in coronagraph observations. Aims. Since no direct observational "ground truth" for the K-corona exists, the amount of coronal signal that is inadvertently removed by background subtraction methods remains unknown. We aim to quantify, for the first time, the impact of background subtraction on the inferred large-scale structure and brightness of the solar corona. Methods. We use a 32-day simulation based on a novel near-real-time, data-assimilative, time-evolving magnetohydrodynamic model to generate synthetic white-light observables. Because these synthetic observations are free from dust and instrumental stray-light contributions, they provide direct access to the "true" K-corona and enable a quantitative assessment of the effects of background subtraction. Results. We find that background subtraction generally preserves the large-scale morphology of the electron corona, including the locations and shapes of major coronal structures. However, the procedure systematically modifies the relative brightness of different features and removes a non-negligible fraction of the K-coronal signal. Conclusions. Although standard background subtraction techniques successfully recover the overall appearance of the electron corona, they can alter its quantitative photometric properties. These findings should be considered when interpreting coronal brightness measurements and deriving physical properties from processed white-light observations.
ER -