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REVIEW 3 major objections 2 minor 124 references

Optimization Algorithm for Determining the Source Surface Radius Based on Parker Solar Probe in situ Measurements from Encounters 1 to 19

T0 review · 3 major / 2 minor · reviewed 2026-07-02 · grok-4.3

Pith's one-line read The optimal source surface radius for PFSS models increases from solar minimum into the ascending phase when tuned to Parker Solar Probe data.

desk verdict The paper gives a concrete optimization procedure for choosing R_ss in PFSS models from PSP data plus a uniqueness proof. read the letter →

arxiv 2607.00459 v1 pith:KIH2K42J submitted 2026-07-01 astro-ph.SR math.OCphysics.space-ph

classification astro-ph.SRmath.OCphysics.space-ph
keywords PFSSmodelsourcesurfaceradiusParkerSolarProbeopenmagneticfluxcycleoptimizationalgorithmpolaritycoronalfield
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper develops an optimization algorithm to locate the best source surface radius in the Potential Field Source Surface model. It minimizes the mean squared error between the model's extrapolated radial field and Parker Solar Probe measurements after Parker spiral backmapping and radial scaling across encounters 1-19. The work proves the forward problem is well-posed and that a unique optimal radius exists. Results show this optimal radius grows as solar cycle 25 moves from minimum into its ascending phase. The tuned radius improves agreement on open flux while preserving or improving magnetic polarity accuracy relative to the fixed value of 2.5 solar radii.

What carries the argument

The mean squared error objective functional between PFSS extrapolation and backmapped, radially scaled Parker Solar Probe radial field measurements, used to optimize the source surface radius.

What would settle it

If the optimal source surface radius fails to increase when the algorithm is rerun on Parker Solar Probe encounters from later in the ascending phase of solar cycle 25, the reported trend would be contradicted.

Watch

Extended reading notes

Core claim

The paper proves the well-posedness of the PFSS forward problem and establishes existence and uniqueness of the optimal source surface radius. It defines the objective functional as the mean squared error between PFSS extrapolation and Parker Solar Probe radial magnetic field measurements after Parker spiral backmapping and radial scaling for Encounters 1-19. The optimization algorithm is validated with an analytical solution and cross-checked with ACE data. The optimal R_ss values generally increase from solar minimum into the ascending phase of solar cycle 25, and the resulting models improve open flux agreement while preserving or improving polarity prediction accuracy relative to 2.5 R_s

Load-bearing premise

The mean squared error between PFSS extrapolation and backmapped PSP radial field measurements after radial scaling accurately captures the true coronal magnetic topology and open flux without significant contamination from local structures or model assumptions in the backmapping procedure.

Editorial extensions

If this is right

  • The optimal source surface radius increases from solar minimum into the ascending phase of solar cycle 25.
  • The optimized PFSS solution improves agreement with observed open flux relative to the standard 2.5 solar radii.
  • Polarity prediction accuracy is preserved or improved compared with the fixed 2.5 solar radii choice.
  • Pareto frontiers show open flux as the dominant metric during solar minimum and polarity accuracy as dominant during the ascending phase.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • A cycle-dependent source surface radius could reduce systematic mismatches in models that currently assume a constant value.
  • The same optimization procedure applied to other in-situ datasets could test whether the radius trend holds at different heliocentric distances.
  • If backmapping assumptions introduce bias, the derived radii may partly reflect those procedural choices rather than purely coronal properties.
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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit.

Referee Report

3 major / 2 minor

Summary. The manuscript develops an optimization algorithm to determine the optimal source surface radius R_ss for PFSS extrapolations by minimizing the mean squared error between the model radial field at the source surface and Parker Solar Probe in-situ measurements (after Parker spiral backmapping and radial scaling) across encounters 1–19. It claims a proof of well-posedness of the PFSS forward problem together with existence and uniqueness of the optimum via compactness and continuity arguments, reports that the resulting optimal R_ss values increase from solar minimum into the ascending phase of cycle 25, and states that the optimized solutions improve open-flux agreement while preserving or improving polarity accuracy relative to the conventional 2.5 R_s choice. Independent validation with ACE data and Pareto analysis of open-flux versus polarity metrics are also presented.

Significance. If the backmapping and scaling assumptions hold, the work supplies a reproducible, data-driven procedure for selecting a solar-cycle-dependent R_ss that could improve open-flux estimates used in space-weather modeling. The explicit proof of well-posedness and the use of an independent ACE cross-validation set are positive features that strengthen the methodological contribution.

major comments (3)
  1. [abstract (objective functional)] Abstract, paragraph on objective functional: the MSE is formed after Parker spiral backmapping and 1/r² radial scaling; no sensitivity tests to the assumed solar-wind speed profile or to possible non-radial flow distortions are reported. Because the headline trend (increasing optimal R_ss with cycle phase) is produced by this minimization, the absence of such tests leaves open the possibility that the reported variation is an artifact of the mapping procedure rather than a signature of changing coronal topology.
  2. [abstract (cross-validation)] Abstract and results on cross-validation: while ACE data are described as an independent validation set, the manuscript does not state whether the R_ss values optimized on PSP encounters are applied unchanged to ACE or whether a separate optimization is performed; without this clarification the claimed independence of the trend confirmation cannot be assessed.
  3. [abstract (well-posedness)] Abstract, well-posedness claim: the compactness-plus-continuity argument establishes existence and uniqueness for the mathematical optimization problem as formulated, yet supplies no argument that the chosen objective functional remains a faithful proxy once local coronal structures or transients (unrepresented by PFSS) contaminate the PSP samples; this gap directly affects the physical interpretation of the optimized R_ss sequence.
minor comments (2)
  1. The admissible set for R_ss and the precise form of the radial-scaling operator should be stated explicitly (including any bounds or discretization) to allow readers to reproduce the compactness argument.
  2. Figure captions and table headings should indicate the exact number of PSP samples retained after quality filtering for each encounter.

Simulated Author's Rebuttal

3 responses · 0 unresolved

We thank the referee for the constructive and detailed report. We address each major comment below, clarifying the manuscript's approach and indicating where revisions will be made.

read point-by-point responses
  1. Referee: [abstract (objective functional)] Abstract, paragraph on objective functional: the MSE is formed after Parker spiral backmapping and 1/r² radial scaling; no sensitivity tests to the assumed solar-wind speed profile or to possible non-radial flow distortions are reported. Because the headline trend (increasing optimal R_ss with cycle phase) is produced by this minimization, the absence of such tests leaves open the possibility that the reported variation is an artifact of the mapping procedure rather than a signature of changing coronal topology.

    Authors: The manuscript does not report sensitivity tests to solar-wind speed profiles or non-radial flows, which is a valid observation. The backmapping follows standard Parker spiral assumptions with a representative speed. In revision we will add an appendix with sensitivity tests using a range of constant speeds (300-600 km/s) and a variable-speed model, quantifying the effect on the optimal R_ss sequence and the reported trend. This will allow readers to assess robustness directly. revision: yes

  2. Referee: [abstract (cross-validation)] Abstract and results on cross-validation: while ACE data are described as an independent validation set, the manuscript does not state whether the R_ss values optimized on PSP encounters are applied unchanged to ACE or whether a separate optimization is performed; without this clarification the claimed independence of the trend confirmation cannot be assessed.

    Authors: The R_ss values optimized on PSP encounters 1-19 were applied unchanged to the corresponding ACE intervals; no separate optimization was performed on ACE. This is the intended meaning of 'independent cross-validation.' We will revise the abstract and Section 4 to state this procedure explicitly, removing any ambiguity about the validation design. revision: yes

  3. Referee: [abstract (well-posedness)] Abstract, well-posedness claim: the compactness-plus-continuity argument establishes existence and uniqueness for the mathematical optimization problem as formulated, yet supplies no argument that the chosen objective functional remains a faithful proxy once local coronal structures or transients (unrepresented by PFSS) contaminate the PSP samples; this gap directly affects the physical interpretation of the optimized R_ss sequence.

    Authors: The compactness-continuity argument establishes existence and uniqueness strictly for the mathematical problem as posed. It does not address whether the MSE remains a faithful proxy when PFSS assumptions are violated by transients or unresolved coronal structure. The manuscript presents the optimized R_ss as an empirical, data-driven choice within the PFSS framework and reports the resulting open-flux improvement as an observed outcome. We will add a limitations paragraph in the discussion acknowledging this gap and its implications for physical interpretation. revision: partial

Circularity Check

0 steps flagged · score 0.0 of 10

No circularity; optimization result is direct empirical output of MSE fit with independent validation

full rationale

The paper defines an objective functional as MSE between PFSS Br (after backmapping/scaling) and PSP data for encounters 1-19, proves mathematical existence/uniqueness of the minimizer via compactness and continuity, applies the algorithm, and reports the resulting trend in optimal R_ss plus open-flux improvement. This is a standard data-driven optimization whose output trend is not forced by definition or prior self-citation; ACE serves as external cross-validation and an analytical solution validates the solver. No step reduces the central claim to its own inputs by construction.

Assumptions & free parameters 1 free parameters · 2 assumptions · 0 invented entities

The central claim rests on the validity of the PFSS potential-field assumption, the accuracy of Parker spiral backmapping and radial scaling for in-situ data, and the choice of MSE as the objective that correctly represents coronal topology.

free parameters (1)
  • R_ss
    The source surface radius is the parameter being optimized via the MSE objective on PSP data.
assumptions (2)
  • domain assumption PFSS forward problem is well-posed with existence and uniqueness of optimal source surface
    Claimed in abstract but not verifiable without full text.
  • domain assumption Backmapping and radial scaling preserve the relevant magnetic field information for comparison
    Central to the objective functional definition.

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Cite this review

Pith. "Pith review of Optimization Algorithm for Determining the Source Surface Radius Based on Parker Solar Probe in situ Measurements from Encounters 1 to 19." pith.science (2026). https://pith.science/paper/KIH2K42J

@misc{pith2026260700459,
  author       = {Pith},
  title        = {Pith review of: Optimization Algorithm for Determining the Source Surface Radius Based on Parker Solar Probe in situ Measurements from Encounters 1 to 19},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/KIH2K42J}},
  note         = {Machine review of arXiv:2607.00459}
}
abstract

The Potential Field Source Surface (PFSS) extrapolation is a method for estimating the large scale coronal magnetic field from photospheric magnetograms. The source surface serves as the outer boundary of its solution domain, and is typically a spherical surface. An appropriate source surface radius ($R_{ss}$) enables more accurate identification of the coronal magnetic field topology and estimation of the open flux, thereby potentially enhancing the accuracy of space weather modeling. We prove the well-posedness of the PFSS forward problem and establish the existence and uniqueness of the optimal source surface by combining compactness of the admissible set with continuity of the objective functional. The objective functional is the mean squared error (MSE) between PFSS extrapolation and Parker Solar Probe (PSP) radial magnetic field measurements after Parker spiral backmapping and radial scaling for Encounters 1-19. The optimization algorithm is validated with an analytical solution, and Advanced Composition Explorer (ACE) in situ measurements are used as an independent cross-validation dataset. Additional evaluation metrics and Pareto analysis are used to identify the dominant metrics between open flux and polarity prediction accuracy. Our results show that the optimal $R_{ss}$ derived from the algorithm generally increase from solar minimum into the ascending phase of solar cycle 25. The optimized solution improves open flux agreement while preserving or improving polarity prediction accuracy relative to $2.5R_{s}$. The Pareto frontiers show a transition for dominant metrics from open flux during solar minimum to polarity prediction accuracy during the ascending phase.

Figures

Figures reproduced from arXiv: 2607.00459 by the authors.

Figure 1
Figure 1. (a) Illustration of the solution domain for PFSS extrapolation with a spherical [PITH_FULL_IMAGE:figures/full_fig_p005_1.png] view at source ↗
Figure 2
Figure 2. (a) Geometric setting of the free boundary problem for PFSS extrapolation. The [PITH_FULL_IMAGE:figures/full_fig_p010_2.png] view at source ↗
Figure 3
Figure 3. (a) PSP/FIELDS radial magnetic field Br measurements in hourly time bins for CR2210, shown as boxplots used in the IQR outlier detection, with outliers marked by open circles. (b) PSP/FIELDS Br after the IQR cleaning and 20 minutes averaging, with red and blue denoting positive and negative polarity, respectively. (c) PSP/SWEAP radial solar wind velocity vr used for Parker spiral backmapping. The orange points show … view at source ↗
Figures from the paper (8 more)
Figure 4
Figure 4. Figure 4: (a) Iteration process for the analytical validation. The blue gray curve shows the [PITH_FULL_IMAGE:figures/full_fig_p019_4.png]
Figure 5
Figure 5. Figure 5: Comparison between BPSP,k r and Bk r for Encounters 1-19. Purple curves show the reference solution with Rss = 2.50Rs, black curves show the optimized solution from Algo￾rithm 1, and red and blue points denote positive and negative BPSP,k r , respectively. –24– [PITH_…
Figure 6
Figure 6. Figure 6: (a) Comparison between BPSP,k r and Bk r for PSP Encounter 1 during solar min￾imum. Red and blue points denote positive and negative BPSP,k r , respectively. The purple dashed curve denotes the reference Bk r with Rss = 2.5Rs, and the black solid curve denotes the opti…
Figure 7
Figure 7. Figure 7: (a) The optimal Rss for PSP Encounters 1-19. The red polyline with square mark￾ers shows the encounter by encounter optimization results, the black curve shows the spline used only to visualize the trend, and the blue curve shows the sunspot number over the same Carrin…
Figure 8
Figure 8. Figure 8: (a) Iteration process for PSP Encounter 9. The blue gray curve shows the evolving [PITH_FULL_IMAGE:figures/full_fig_p027_8.png]
Figure 9
Figure 9. Figure 9: (a) Open flux and polarity prediction accuracy for the PSP based evaluation. The [PITH_FULL_IMAGE:figures/full_fig_p028_9.png]
Figure 10
Figure 10. Figure 10: (a) Pareto analysis for PSP Encounter 17 in parameter space. The blue curve [PITH_FULL_IMAGE:figures/full_fig_p030_10.png]
Figure 11
Figure 11. Figure 11: Pareto frontiers for PSP Encounters 1-19 calculated with Algorithm 2. In each [PITH_FULL_IMAGE:figures/full_fig_p031_11.png]

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Reference graph

Works this paper leans on

124 extracted references · 124 canonical work pages

  1. [1]

    Dynamics of the Interplanetary Gas and Magnetic Fields.

    Dynamics of the Interplanetary Gas and Magnetic Fields. The Astrophysical Journal , year = 1958, month = nov, volume =. doi:10.1086/146579 , adsurl =

  2. [2]

    The Solar Probe Plus Mission: Humanity’s First Visit to Our Star

    The. Space Science Reviews , author =. 2016 , pages =. doi:10.1007/s11214-015-0211-6 , abstract =

  3. [3]

    Parker Solar Probe: Four Years of Discoveries at Solar Cycle Minimum

    Parker. Space Science Reviews , author =. 2023 , pages =. doi:10.1007/s11214-023-00952-4 , abstract =

  4. [4]

    Highly structured slow solar wind emerging from an equatorial coronal hole

    Highly structured slow solar wind emerging from an equatorial coronal hole , volume =. Nature , author =. 2019 , pages =. doi:10.1038/s41586-019-1818-7 , abstract =

  5. [5]

    Nat Astron , year = 2024, month = oct, volume =

    The origin of interplanetary switchbacks in reconnection at chromospheric network boundaries , volume =. Nature Astronomy , author =. 2024 , pages =. doi:10.1038/s41550-024-02321-9 , abstract =

  6. [6]

    Astrophys J Lett , keywords =

    Hou, Chuanpeng and Rouillard, Alexis P. and He, Jiansen and Gannouni, Bahaeddine and Réville, Victor and Louarn, Philippe and Fedorov, Andrey and Přech, Lubomír and Owen, Christopher J. and Verscharen, Daniel and D’Amicis, Raffaella and Sorriso-Valvo, Luca and Fargette, Naïs and Coburn, Jesse and Génot, Vincent and Raines, Jim M. and Bruno, Roberto and Li...

  7. [7]

    T., & Roelof, E

    Large-Scale Structure of the Interplanetary Medium, I: High Coronal Source Longitude of the Quiet-Time Solar Wind. Solar Physics , keywords =. doi:10.1007/BF00152395 , adsurl =

  8. [8]

    and Badman, S

    Dakeyo, J.B. and Badman, S. T. and Rouillard, A. P. and Réville, V. and Verscharen, D. and Démoulin, P. and Maksimovic, M. , title =. doi:10.1051/0004-6361/202348892

Show all 124 references
  1. [9]

    and Dolla, L

    Koukras, A. and Dolla, L. and Keppens, R. , title =. doi:10.1051/0004-6361/202244327

  2. [10]

    and Froment, C

    Bizien, N. and Froment, C. and Madjarska, M. S. and Dudok de Wit, T. and Velli, M. , title =. doi:10.1051/0004-6361/202452140

  3. [11]

    and Brooks, David H

    Badman, Samuel T. and Brooks, David H. and Poirier, Nicolas and Warren, Harry P. and Petrie, Gordon and Rouillard, Alexis P. and Nick Arge, C. and Bale, Stuart D. and de Pablos Agüero, Diego and Harra, Louise and Jones, Shaela I. and Kouloumvakos, Athanasios and Riley, Pete an...

  4. [12]

    Solar Physics , author =

    A model of interplanetary and coronal magnetic fields , volume =. Solar Physics , author =. 1969 , pages =. doi:10.1007/BF00146478 , abstract =

  5. [13]

    Solar Physics , author =

    Magnetic fields and the structure of the solar corona , volume =. Solar Physics , author =. 1969 , pages =. doi:10.1007/BF00145734 , abstract =

  6. [14]

    Todd and Wilcox, John M

    Hoeksema, J. Todd and Wilcox, John M. and Scherrer, Philip H. , title =. Journal of Geophysical Research: Space Physics , volume =. doi:https://doi.org/10.1029/JA088iA12p09910 , url =. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/JA088iA12p09910 , abstract =

  7. [15]

    AIP Conference Proceedings , author =

    Improved. AIP Conference Proceedings , author =. 2003 , note =. doi:10.1063/1.1618574 , abstract =

  8. [16]

    Journal of Geophysical Research: Space Physics , volume =

    Poduval, Bala and Zhao, Xue Pu , title =. Journal of Geophysical Research: Space Physics , volume =. doi:https://doi.org/10.1029/2004JA010384 , url =. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2004JA010384 , abstract =

  9. [17]

    Improvement to the global distribution of coronal plasma and magnetic field on the source surface using expansion factor fs and angular distance Thetab , journal =

    Fang Shen and Xueshang Feng and Changqing Xiang , keywords =. Improvement to the global distribution of coronal plasma and magnetic field on the source surface using expansion factor fs and angular distance Thetab , journal =. 2012 , issn =. doi:https://doi.org/10.1016/j.jastp...

  10. [18]

    Journal of Physics: Conference Series , abstract =

    Yalim, Mehmet Sarp and Pogorelov, Nikolai and Liu, Yang , title =. Journal of Physics: Conference Series , abstract =. 2017 , month =. doi:10.1088/1742-6596/837/1/012015 , url =

  11. [19]

    The Astrophysical Journal , abstract =

    Liu, Yousheng and Shen, Fang and Yang, Yi , title =. The Astrophysical Journal , abstract =. 2019 , month =. doi:10.3847/1538-4357/ab543e , url =

  12. [20]

    and Rouillard, A

    Dakeyo, J.B. and Rouillard, A. P. and Réville, V. and Démoulin, P. and Maksimovic, M. and Chapiron, A. and Pinto, R. F. and Louarn, P. , title =. doi:10.1051/0004-6361/202451272

  13. [21]

    Shen, Fang and Feng, Xueshang and Wu, S. T. and Xiang, Changqing , title =. Journal of Geophysical Research: Space Physics , volume =. doi:https://doi.org/10.1029/2006JA012164 , url =. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2006JA012164 , abstract =

  14. [22]

    The statistical and numerical study of the global distribution of coronal plasma and magnetic field near 2.5Rs over a 10-year period , journal =

    Fang Shen and Xueshang Feng and Changqing Xiang and Wenbin Song , keywords =. The statistical and numerical study of the global distribution of coronal plasma and magnetic field near 2.5Rs over a 10-year period , journal =. 2010 , issn =. doi:https://doi.org/10.1016/j.jastp.20...

  15. [23]

    and Feng, X

    Shen, F. and Feng, X. S. and Wu, S. T. and Xiang, C. Q. and Song, W. B. , title =. Journal of Geophysical Research: Space Physics , volume =. doi:https://doi.org/10.1029/2010JA015809 , url =. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2010JA015809 , abstract =

  16. [24]

    and Feng, X

    Shen, F. and Feng, X. S. and Wang, Yuming and Wu, S. T. and Song, W. B. and Guo, J. P. and Zhou, Y. F. , title =. Journal of Geophysical Research: Space Physics , volume =. doi:https://doi.org/10.1029/2011JA016584 , url =. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.102...

  17. [25]

    The Astrophysical Journal , abstract =

    Shen, Fang and Yang, Zicai and Zhang, Jie and Wei, Wenwen and Feng, Xueshang , title =. The Astrophysical Journal , abstract =. 2018 , month =. doi:10.3847/1538-4357/aad806 , url =

  18. [26]

    The Astrophysical Journal Letters , abstract =

    Zhao, Lulu and Zhang, Ming , title =. The Astrophysical Journal Letters , abstract =. 2018 , month =. doi:10.3847/2041-8213/aac6cf , url =

  19. [27]

    Modeling solar energetic particle transport in 3D background solar wind: Influences of the compression regions , journal =

    Wenwen Wei and Fang Shen and Zicai Yang and Lulu Zhao and Yang Wang and Pingbing Zuo and Jie Zhang , keywords =. Modeling solar energetic particle transport in 3D background solar wind: Influences of the compression regions , journal =. 2019 , issn =. doi:https://doi.org/10.10...

  20. [28]

    Universe , VOLUME =

    Zhu, Yuji and Shen, Fang , TITLE =. Universe , VOLUME =. 2024 , NUMBER =

  21. [29]

    The Astrophysical Journal , abstract =

    Park, Jinhye and Bucik, Radoslav and Jeong, Hyun-Jin and Moon, Yong-Jae , title =. The Astrophysical Journal , abstract =. 2024 , month =. doi:10.3847/1538-4357/ad843e , url =

  22. [30]

    The Astrophysical Journal , abstract =

    Zhao, Jiutong and Wang, Shan and Sun, Weijie and Zhu, Xingyu and Hou, Chuanpeng and Zong, Qiugang and He, Jiansen and Zhou, Xuzhi and Yue, Chao and Yang, Liu , title =. The Astrophysical Journal , abstract =. 2025 , month =. doi:10.3847/1538-4357/ad9b28 , url =

  23. [31]

    and Qiu, J

    Lowder, C. and Qiu, J. and Leamon, R. and Liu, Y. , title =. The Astrophysical Journal , abstract =. 2014 , month =. doi:10.1088/0004-637X/783/2/142 , url =

  24. [32]

    Journal of Geophysical Research: Space Physics , volume =

    Hayashi, Keiji and Yang, Shangbin and Deng, Yuagyong , title =. Journal of Geophysical Research: Space Physics , volume =. doi:https://doi.org/10.1002/2015JA021757 , url =. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2015JA021757 , abstract =

  25. [34]

    Solar Physics , author =

    Coronal. Solar Physics , author =. 2011 , pages =. doi:10.1007/s11207-010-9699-9 , abstract =

  26. [35]

    Arden, W. M. and Norton, A. A. and Sun, X. , title =. Journal of Geophysical Research: Space Physics , volume =. doi:https://doi.org/10.1002/2013JA019464 , url =. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2013JA019464 , abstract =

  27. [36]

    , title =

    Nikolic, L. , title =. Space Weather , volume =. doi:https://doi.org/10.1029/2019SW002205 , url =. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2019SW002205 , abstract =

  28. [37]

    The Astrophysical Journal , abstract =

    Boe, Benjamin and Habbal, Shadia and Druckmüller, Miloslav , title =. The Astrophysical Journal , abstract =. 2020 , month =. doi:10.3847/1538-4357/ab8ae6 , url =

  29. [38]

    Habbal, Shadia R. and Druckmüller, Miloslav and Alzate, Nathalia and Ding, Adalbert and Johnson, Judd and Starha, Pavel and Hoderova, Jana and Boe, Benjamin and Constantinou, Sage and Arndt, Martina , title =. The Astrophysical Journal Letters , abstract =. 2021 , month =. doi...

  30. [39]

    The Astrophysical Journal , abstract =

    Benavitz, Luke Fushimi and Boe, Benjamin and Habbal, Shadia Rifai , title =. The Astrophysical Journal , abstract =. 2024 , month =. doi:10.3847/1538-4357/ad71c6 , url =

  31. [40]

    Koskela, J. S. and Virtanen, I. I. and Mursula, K. , title =. Astronomy Astrophysics , year =. doi:10.1051/0004-6361/201832609

  32. [41]

    doi:10.1051/0004-6361/201935713

    Virtanen, Ilpo and Mursula, Kalevi , title =. doi:10.1051/0004-6361/201935713

  33. [42]

    doi:10.1051/0004-6361/201935967

    Koskela, Jennimari and Virtanen, Ilpo and Mursula, Kalevi , title =. doi:10.1051/0004-6361/201935967

  34. [43]

    and Heinemann, S

    Asvestari, E. and Heinemann, S. G. and Temmer, M. and Pomoell, J. and Kilpua, E. and Magdalenic, J. and Poedts, S. , title =. Journal of Geophysical Research: Space Physics , volume =. doi:https://doi.org/10.1029/2019JA027173 , url =. https://agupubs.onlinelibrary.wiley.com/do...

  35. [44]

    Journal of Geophysical Research: Space Physics , volume =

    Li, Huichao and Feng, Xueshang and Wei, Fengsi , title =. Journal of Geophysical Research: Space Physics , volume =. doi:https://doi.org/10.1029/2020JA028870 , url =. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2020JA028870 , note =

  36. [45]

    Finley, A. J. and Brun, A. S. , title =. doi:10.1051/0004-6361/202245642

  37. [46]

    doi:10.1051/0004-6361/202451267

    Tähtinen, Ismo and Asikainen, Timo and Mursula, Kalevi , title =. doi:10.1051/0004-6361/202451267

  38. [47]

    2024 , pages =

    The Astrophysical Journal , author =. 2024 , pages =. doi:10.3847/1538-4357/ad7d00 , abstract =

  39. [48]

    and Landi, Simone and Matteini, Lorenzo and Bale, Stuart

    Bercic, Laura and Larson, Davin and Whittlesey, Phyllis and Maksimovic, Milan and Badman, Samuel T. and Landi, Simone and Matteini, Lorenzo and Bale, Stuart. D. and Bonnell, John W. and Case, Anthony W. and Dudok de Wit, Thierry and Goetz, Keith and Harvey, Peter R. and Kasper...

  40. [49]

    Badman and Stuart D

    Samuel T. Badman and Stuart D. Bale and Juan C. Martínez Oliveros and Olga Panasenco and Marco Velli and David Stansby and Juan C. Buitrago-Casas and Victor Réville and John W. Bonnell and Anthony W. Case and Thierry Dudok de Wit and Keith Goetz and Peter R. Harvey and Justin ...

  41. [50]

    Solar Physics , author =

    Searching for a. Solar Physics , author =. 2022 , pages =. doi:10.1007/s11207-022-02022-4 , abstract =

  42. [51]

    Solar Physics , author =

    Coronal magnetic-field model with non-spherical source surface , volume =. Solar Physics , author =. 1978 , pages =. doi:10.1007/BF00152334 , abstract =

  43. [52]

    Solar Physics , author =

    Simulation of the magnetic structure of the inner heliosphere by means of a non-spherical source surface , volume =. Solar Physics , author =. 1982 , pages =. doi:10.1007/BF00156118 , abstract =

  44. [53]

    , TITLE =

    Schulz, M. , TITLE =. Annales Geophysicae , VOLUME =. 1997 , NUMBER =

  45. [54]

    and Badman, Samuel T

    Panasenco, Olga and Velli, Marco and D’Amicis, Raffaella and Shi, Chen and Réville, Victor and Bale, Stuart D. and Badman, Samuel T. and Kasper, Justin and Korreck, Kelly and Bonnell, J. W. and Wit, Thierry Dudok de and Goetz, Keith and Harvey, Peter R. and MacDowall, Robert J...

  46. [55]

    and Heidrich-Meisner, V

    Kruse, M. and Heidrich-Meisner, V. and Wimmer-Schweingruber, R. F. and Hauptmann, M. , title =. doi:10.1051/0004-6361/202037734

  47. [56]

    and Heidrich-Meisner, V

    Kruse, M. and Heidrich-Meisner, V. and Wimmer-Schweingruber, R. F. , title =. Astronomy Astrophysics , volume =. doi:10.1051/0004-6361/202039120

  48. [57]

    Finite Element Methods

    Kang, Feng and Zhong-Ci, Shi. Finite Element Methods. Mathematical Theory of Elastic Structures. 1996. doi:10.1007/978-3-662-03286-2_5

  49. [58]

    Shape Sensitivity Analysis of Variational Inequalities

    Sokolowski, Jan and Zolesio, Jean-Paul. Shape Sensitivity Analysis of Variational Inequalities. Introduction to Shape Optimization: Shape Sensitivity Analysis. 1992. doi:10.1007/978-3-642-58106-9_4

  50. [59]

    Chapter 19 - Multiobjective Optimization and Advanced Topics , editor =

    Kuang-Hua Chang , keywords =. Chapter 19 - Multiobjective Optimization and Advanced Topics , editor =. e-Design , publisher =. 2015 , isbn =. doi:https://doi.org/10.1016/B978-0-12-382038-9.00019-3 , url =

  51. [60]

    2008 , publisher=

    Partial Differential Equations: An Introduction , author=. 2008 , publisher=

  52. [61]

    2010 , publisher=

    Partial Differential Equations , author=. 2010 , publisher=

  53. [62]

    The Astrophysical Journal , abstract =

    Toth, Gábor and van der Holst, Bart and Huang, Zhenguang , title =. The Astrophysical Journal , abstract =. 2011 , month =. doi:10.1088/0004-637X/732/2/102 , url =

  54. [63]

    u hrung. Maschinenbau (TI-58/59, HP-41 C, FX-502/602 P): Verbindungstechnik, Verformungstechnik, Getriebetechnik, W \

    Alt, Helmut and Schumny, Harald. Einf \"u hrung. Maschinenbau (TI-58/59, HP-41 C, FX-502/602 P): Verbindungstechnik, Verformungstechnik, Getriebetechnik, W \"a rmeabfuhr. 1984. doi:10.1007/978-3-322-85906-8_1

  55. [64]

    Peichl , keywords =

    Kazufumi Ito and Karl Kunisch and Gunther H. Peichl , keywords =. Variational approach to shape derivatives for a class of Bernoulli problems , journal =. 2006 , issn =. doi:https://doi.org/10.1016/j.jmaa.2005.03.100 , url =

  56. [65]

    Nonlinear integral equations for Bernoulli’s free boundary value problem in three dimensions , journal =

    Olha. Nonlinear integral equations for Bernoulli’s free boundary value problem in three dimensions , journal =. 2017 , note =. doi:https://doi.org/10.1016/j.camwa.2017.06.011 , url =

  57. [66]

    , author =

    Existence and regularity for a minimum problem with free boundary. , author =. Journal für die reine und angewandte Mathematik , doi =. 1981 , lastchecked =

  58. [67]

    Jahresbericht der Deutschen Mathematiker-Vereinigung , author =

    Antoine. Jahresbericht der Deutschen Mathematiker-Vereinigung , author =. 2019 , pages =. doi:10.1365/s13291-018-00195-1 , number =

  59. [68]

    1986 , issn =

    Mixed boundary value problems for elliptic and parabolic differential equations of second order , journal =. 1986 , issn =. doi:https://doi.org/10.1016/0022-247X(86)90314-8 , url =

  60. [69]

    Computational Optimization and Applications , author =

    A second-order shape optimization algorithm for solving the exterior. Computational Optimization and Applications , author =. 2020 , pages =. doi:10.1007/s10589-020-00199-7 , abstract =

  61. [70]

    Solar Physics , author =

    Comparative. Solar Physics , author =. 2014 , pages =. doi:10.1007/s11207-013-0421-6 , abstract =

  62. [71]

    Evolution Equations and Control Theory , author =

    A new energy-gap cost functional approach for the exterior Bernoulli free boundary problem , volume =. Evolution Equations and Control Theory , author =. 2019 , pages =. doi:10.3934/eect.2019038 , abstract =

  63. [72]

    1975 , issn =

    On the existence of a solution in a domain identification problem , journal =. 1975 , issn =. doi:https://doi.org/10.1016/0022-247X(75)90091-8 , url =

  64. [73]

    J. W. Harvey and F. Hill and R. P. Hubbard and J. R. Kennedy and J. W. Leibacher and J. A. Pintar and P. A. Gilman and R. W. Noyes and A. M. Title and J. Toomre and R. K. Ulrich and A. Bhatnagar and J. A. Kennewell and W. Marquette and J. Patrón and O. Saá and E. Yasukawa , ti...

  65. [74]

    Solar Physics , author =

    The. Solar Physics , author =. 2012 , pages =. doi:10.1007/s11207-011-9841-3 , abstract =

  66. [75]

    Solar Physics , author =

    The. Solar Physics , author =. 2012 , pages =. doi:10.1007/s11207-011-9834-2 , abstract =

  67. [76]

    , title =

    Tukey, John W. , title =. 1977 , publisher =

  68. [77]

    Space Weather , volume =

    Yang, Yi and Shen, Fang and Yang, Zicai and Feng, Xueshang , title =. Space Weather , volume =. doi:https://doi.org/10.1029/2018SW001955 , url =. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2018SW001955 , abstract =

  69. [78]

    Solar Physics , author =

    Modeling the. Solar Physics , author =. 2019 , pages =. doi:10.1007/s11207-019-1496-5 , abstract =

  70. [79]

    Space Weather , volume =

    Lin, Rong and Luo, Zhekai and He, Jiansen and Xie, Lun and Hou, Chuanpeng and Chen, Shuwei , title =. Space Weather , volume =. doi:https://doi.org/10.1029/2023SW003561 , url =. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2023SW003561 , note =

  71. [80]

    Pareto Optimality

    Ng, Yew-Kwang. Pareto Optimality. Welfare Economics: Towards a More Complete Analysis. 2004. doi:10.1057/9781403944061_2

  72. [81]

    Regularization for Deep Learning: A Taxonomy , doi =

    Kukacka, Jan and Golkov, Vladimir and Cremers, Daniel , year =. Regularization for Deep Learning: A Taxonomy , doi =

  73. [82]

    ArXiv , year=

    Efficient Natural Gradient Descent Methods for Large-Scale Optimization Problems , author=. ArXiv , year=

  74. [83]

    Raissi and P

    M. Raissi and P. Perdikaris and G.E. Karniadakis , keywords =. Physics-informed neural networks: A deep learning framework for solving forward and inverse problems involving nonlinear partial differential equations , journal =. 2019 , issn =. doi:https://doi.org/10.1016/j.jcp....

  75. [84]

    A physics-informed learning approach to Bernoulli-type free boundary problems , journal =

    Salvatore Cuomo and Fabio Giampaolo and Stefano Izzo and Carlo Nitsch and Francesco Piccialli and Cristina Trombetti , keywords =. A physics-informed learning approach to Bernoulli-type free boundary problems , journal =. 2022 , issn =. doi:https://doi.org/10.1016/j.camwa.2022...

  76. [85]

    Scientific Reports , author =

    Optimal approximations for the free boundary problems of the space-time fractional. Scientific Reports , author =. 2024 , pages =. doi:10.1038/s41598-024-77073-7 , abstract =

  77. [86]

    Dierckx , abstract =

    P. Dierckx , abstract =. An algorithm for smoothing, differentiation and integration of experimental data using spline functions , journal =. 1975 , issn =. doi:https://doi.org/10.1016/0771-050X(75)90034-0 , url =

  78. [87]

    , Title =

    Miettinen, Kaisa M. , Title =. 1999 , Publisher =

  79. [88]

    2001 , Publisher =

    Deb, Kalyanmoy , Title =. 2001 , Publisher =

  80. [89]

    and Downs, Cooper and Linker, Jon A

    Caplan, Ronald M. and Downs, Cooper and Linker, Jon A. and Mikic, Zoran , title =. The Astrophysical Journal , abstract =. 2021 , month =. doi:10.3847/1538-4357/abfd2f , url =

  81. [90]

    Frontiers in Astronomy and Space Sciences , VOLUME=

    Liu, XiaoJing and Feng, Xueshang and Lv, Jiakun and Wang, Xinyi and Zhang, Man , TITLE=. Frontiers in Astronomy and Space Sciences , VOLUME=. 2022 , URL=. doi:10.3389/fspas.2022.1055969 , ISSN=

  82. [91]

    2022 , eprint=

    Test Problems for Potential Field Source Surface Extrapolations of Solar and Stellar Magnetic Fields , author=. 2022 , eprint=

  83. [92]

    Linker, J. A. and Caplan, R. M. and Downs, C. and Riley, P. and Mikic, Z. and Lionello, R. and Henney, C. J. and Arge, C. N. and Liu, Y. and Derosa, M. L. and Yeates, A. and Owens, M. J. , title =. The Astrophysical Journal , abstract =. 2017 , month =. doi:10.3847/1538-4357/a...

  84. [93]

    2020 , eprint=

    Measurement of the Open Magnetic Flux in the Inner Heliosphere down to 0.13AU , author=. 2020 , eprint=. doi:https://doi.org/10.1051/0004-6361/202039407 , url=

  85. [94]

    Research in Astronomy and Astrophysics , abstract =

    Yang, Shuhong and Jiang, Jie and Wang, Zifan and Hou, Yijun and Jin, Chunlan and Song, Qiao and Luo, Yukun and Li, Ting and Zhang, Jun and Zhang, Yuzong and Zhou, Guiping and Deng, Yuanyong and Wang, Jingxiu , title =. Research in Astronomy and Astrophysics , abstract =. 2024 ...

  86. [95]

    and Robbrecht, E

    Wang, Y.-M. and Robbrecht, E. and Sheeley, N. R. , title =. The Astrophysical Journal , abstract =. 2009 , month =. doi:10.1088/0004-637X/707/2/1372 , url =

  87. [96]

    Solar Physics , author =

    Using. Solar Physics , author =. 2014 , pages =. doi:10.1007/s11207-014-0541-7 , abstract =

  88. [97]

    and Bryans, P

    Hahn, M. and Bryans, P. and Landi, E. and Miralles, M. P. and Savin, D. W. , title =. The Astrophysical Journal , abstract =. 2010 , month =. doi:10.1088/0004-637X/725/1/774 , url =

  89. [98]

    Evolutionary features of polar and non-polar coronal holes during solar cycle 24 and the rising phase of cycle 25 , journal =

    Olga Andreeva , keywords =. Evolutionary features of polar and non-polar coronal holes during solar cycle 24 and the rising phase of cycle 25 , journal =. 2023 , note =. doi:https://doi.org/10.1016/j.asr.2022.07.043 , url =

  90. [99]

    Solar Physics , author =

    On. Solar Physics , author =. 2019 , pages =. doi:10.1007/s11207-019-1520-9 , abstract =

  91. [100]

    Romeo, O. M. and Braga, C. R. and Badman, S. T. and Larson, D. E. and Stevens, M. L. and Huang, J. and Phan, T. and Rahmati, A. and Livi, R. and Alnussirat, S. T. and Whittlesey, P. L. and Szabo, A. and Klein, K. G. and Niembro-Hernandez, T. and Paulson, K. and Verniero, J. L....

  92. [101]

    and Badman, Samuel T

    Ervin, Tamar and Bale, Stuart D. and Badman, Samuel T. and Bowen, Trevor A. and Riley, Pete and Paulson, Kristoff and Rivera, Yeimy J. and Romeo, Orlando and Sioulas, Nikos and Larson, Davin and Verniero, Jaye L. and Dewey, Ryan M. and Huang, Jia , title =. The Astrophysical J...

  93. [102]

    Monthly Notices of the Royal Astronomical Society , volume =

    Wang, Xiaofan and Su, Jiangtao and Zhang, Hongqi , title =. Monthly Notices of the Royal Astronomical Society , volume =. doi:https://doi.org/10.1111/j.1365-2966.2010.16745.x , url =. https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-2966.2010.16745.x , abstract =

  94. [103]

    Nick and Leisner, Andrew and Antiochos, Spiro K

    Arge, C. Nick and Leisner, Andrew and Antiochos, Spiro K. and Wallace, Samantha and Henney, Carl J. , title =. The Astrophysical Journal , abstract =. 2024 , month =. doi:10.3847/1538-4357/ad20e2 , url =

  95. [104]

    and Heinemann, Stephan G

    Linker, Jon A. and Heinemann, Stephan G. and Temmer, Manuela and Owens, Mathew J. and Caplan, Ronald M. and Arge, Charles N. and Asvestari, Eleanna and Delouille, Veronique and Downs, Cooper and Hofmeister, Stefan J. and Jebaraj, Immanuel C. and Madjarska, Maria S. and Pinto, ...

  96. [105]

    and Linker, Jon A

    Asvestari, Eleanna and Temmer, Manuela and Caplan, Ronald M. and Linker, Jon A. and Heinemann, Stephan G. and Pinto, Rui F. and Henney, Carl J. and Arge, Charles N. and Owens, Mathew J. and Madjarska, Maria S. and Pomoell, Jens and Hofmeister, Stefan J. and Scolini, Camilla an...

  97. [106]

    Space Science Reviews , author =

    The. Space Science Reviews , author =. 1998 , pages =. doi:10.1023/A:1005082526237 , abstract =

  98. [107]

    , title =

    Huang, Zhenguang and Tóth, Gábor and Huang, Jia and Sachdeva, Nishtha and van der Holst, Bart and Manchester, Ward B. , title =. The Astrophysical Journal Letters , abstract =. 2024 , month =. doi:10.3847/2041-8213/ad3547 , url =

  99. [108]

    doi:10.5281/zenodo.17129425 , url =

    Wang, Shiouhe , title =. doi:10.5281/zenodo.17129425 , url =

  100. [109]

    2025 , howpublished =

    Wang, Shiouhe , title =. 2025 , howpublished =

  101. [110]

    Harris and K

    Charles R. Harris and K. Jarrod Millman and St. Array programming with. 2020 , month = sep, journal =. doi:10.1038/s41586-020-2649-2 , publisher =

  102. [111]

    and Haberland, Matt and Reddy, Tyler and Cournapeau, David and Burovski, Evgeni and Peterson, Pearu and Weckesser, Warren and Bright, Jonathan and

    Virtanen, Pauli and Gommers, Ralf and Oliphant, Travis E. and Haberland, Matt and Reddy, Tyler and Cournapeau, David and Burovski, Evgeni and Peterson, Pearu and Weckesser, Warren and Bright, Jonathan and. Nature Methods , year =

  103. [112]

    Hunter, J. D. , Title =. Computing in Science & Engineering , Volume =

  104. [113]

    The Astrophysical Journal , keywords =

    The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package. The Astrophysical Journal , keywords =. doi:10.3847/1538-4357/ac7c74 , archivePrefix =. 2206.14220 , primaryClass =

  105. [114]

    doi:10.3847/1538-4357/ab4f7a , url =

    The SunPy Project: Open Source Development and Status of the Version 1.0 Core Package , journal =. doi:10.3847/1538-4357/ab4f7a , url =

  106. [115]

    Müller, D. and St. Cyr, O. C. and Zouganelis, I. and Gilbert, H. R. and Marsden, R. and Nieves-Chinchilla, T. and Antonucci, E. and Auchère, F. and Berghmans, D. and Horbury, T. S. and Howard, R. A. and Krucker, S. and Maksimovic, M. and Owen, C. J. and Rochus, P. and Rodrigue...

  107. [116]

    , title =

    Tepper, David E. , title =. SIAM Journal on Mathematical Analysis , volume =. 1975 , doi =. https://doi.org/10.1137/0506045 , abstract =

  108. [117]

    Archive for Rational Mechanics and Analysis , author =

    Interior free boundary problems for the. Archive for Rational Mechanics and Analysis , author =. 1981 , pages =. doi:10.1007/BF00250477 , number =

  109. [118]

    and Kasper, Justin C

    Livi, Roberto and Larson, Davin E. and Kasper, Justin C. and Abiad, Robert and Case, A. W. and Klein, Kristopher G. and Curtis, David W. and Dalton, Gregory and Stevens, Michael and Korreck, Kelly E. and Ho, George and Robinson, Miles and Tiu, Chris and Whittlesey, Phyllis L. ...

  110. [119]

    Space Science Reviews , author =

    Solar. Space Science Reviews , author =. 2016 , pages =. doi:10.1007/s11214-015-0206-3 , abstract =

  111. [120]

    Space Science Reviews , author =

    The. Space Science Reviews , author =. 2016 , pages =. doi:10.1007/s11214-016-0244-5 , abstract =

  112. [121]

    and Marsden, Richard G

    Smith, Edward J. and Marsden, Richard G. , title =. Geophysical Research Letters , volume =. doi:https://doi.org/10.1029/2003GL018223 , url =. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2003GL018223 , abstract =

  113. [122]

    Solar Physics , author =

    Nonlinear. Solar Physics , author =. 2006 , pages =. doi:10.1007/s11207-006-0068-7 , abstract =

  114. [123]

    and Balogh, A

    Smith, Edward J. and Balogh, A. , title =. Geophysical Research Letters , volume =. doi:https://doi.org/10.1029/95GL02826 , url =. https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/95GL02826 , abstract =

  115. [124]

    AIP Conference Proceedings , author =

    Open. AIP Conference Proceedings , author =. 2003 , note =. doi:10.1063/1.1618543 , abstract =

  116. [125]

    Badman, S. T. and Riley, P. and Jones, S. I. and Kim, T. K. and Allen, R. C. and Arge, C. N. and Bale, S. D. and Henney, C. J. and Kasper, J. C. and Mostafavi, P. and Pogorelov, N. V. and Raouafi, N. E. and Stevens, M. L. and Verniero, J. L. , title =. Journal of Geophysical R...

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