Modeling the Subsurface Structure of Sunspots

H. Moradi, C. Baldner, A. C. Birch, D. C. Braun, R. H. Cameron, T. L. Duvall, Laurent Gizon, D. Haber, Shravan Hanasoge, B. W. Hindman, J. Jackiewicz, E. Khomenko, R. Komm, P. Rajaguru, M. Rempel, M. Roth, R. Schlichenmaier, H. Schunker, H. C. Spruit, K. G. Strassmeier & 2 others M. J. Thompson, S. Zharkov

Research output: Contribution to journalArticle

Abstract

While sunspots are easily observed at the solar surface, determining their subsurface structure is not trivial. There are two main hypotheses for the subsurface structure of sunspots: the monolithic model and the cluster model. Local helioseismology is the only means by which we can investigate subphotospheric structure. However, as current linear inversion techniques do not yet allow helioseismology to probe the internal structure with sufficient confidence to distinguish between the monolith and cluster models, the development of physically realistic sunspot models are a priority for helioseismologists. This is because they are not only important indicators of the variety of physical effects that may influence helioseismic inferences in active regions, but they also enable detailed assessments of the validity of helioseismic interpretations through numerical forward modeling. In this article, we provide a critical review of the existing sunspot models and an overview of numerical methods employed to model wave propagation through model sunspots. We then carry out a helioseismic analysis of the sunspot in Active Region 9787 and address the serious inconsistencies uncovered by Gizon et al. (2009a, 2009b). We find that this sunspot is most probably associated with a shallow, positive wave-speed perturbation (unlike the traditional two-layer model) and that travel-time measurements are consistent with a horizontal outflow in the surrounding moat.

Original languageEnglish (US)
Pages (from-to)1-62
Number of pages62
JournalSolar Physics
Volume267
Issue number1
DOIs
StatePublished - Nov 1 2010

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sunspots
sunspot
modeling
helioseismology
forward modeling
inference
numerical method
travel time
wave propagation
travel
confidence
outflow
time measurement
probe
perturbation
inversions
probes

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Moradi, H., Baldner, C., Birch, A. C., Braun, D. C., Cameron, R. H., Duvall, T. L., ... Zharkov, S. (2010). Modeling the Subsurface Structure of Sunspots. Solar Physics, 267(1), 1-62. https://doi.org/10.1007/s11207-010-9630-4

Modeling the Subsurface Structure of Sunspots. / Moradi, H.; Baldner, C.; Birch, A. C.; Braun, D. C.; Cameron, R. H.; Duvall, T. L.; Gizon, Laurent; Haber, D.; Hanasoge, Shravan; Hindman, B. W.; Jackiewicz, J.; Khomenko, E.; Komm, R.; Rajaguru, P.; Rempel, M.; Roth, M.; Schlichenmaier, R.; Schunker, H.; Spruit, H. C.; Strassmeier, K. G.; Thompson, M. J.; Zharkov, S.

In: Solar Physics, Vol. 267, No. 1, 01.11.2010, p. 1-62.

Research output: Contribution to journalArticle

Moradi, H, Baldner, C, Birch, AC, Braun, DC, Cameron, RH, Duvall, TL, Gizon, L, Haber, D, Hanasoge, S, Hindman, BW, Jackiewicz, J, Khomenko, E, Komm, R, Rajaguru, P, Rempel, M, Roth, M, Schlichenmaier, R, Schunker, H, Spruit, HC, Strassmeier, KG, Thompson, MJ & Zharkov, S 2010, 'Modeling the Subsurface Structure of Sunspots', Solar Physics, vol. 267, no. 1, pp. 1-62. https://doi.org/10.1007/s11207-010-9630-4
Moradi H, Baldner C, Birch AC, Braun DC, Cameron RH, Duvall TL et al. Modeling the Subsurface Structure of Sunspots. Solar Physics. 2010 Nov 1;267(1):1-62. https://doi.org/10.1007/s11207-010-9630-4
Moradi, H. ; Baldner, C. ; Birch, A. C. ; Braun, D. C. ; Cameron, R. H. ; Duvall, T. L. ; Gizon, Laurent ; Haber, D. ; Hanasoge, Shravan ; Hindman, B. W. ; Jackiewicz, J. ; Khomenko, E. ; Komm, R. ; Rajaguru, P. ; Rempel, M. ; Roth, M. ; Schlichenmaier, R. ; Schunker, H. ; Spruit, H. C. ; Strassmeier, K. G. ; Thompson, M. J. ; Zharkov, S. / Modeling the Subsurface Structure of Sunspots. In: Solar Physics. 2010 ; Vol. 267, No. 1. pp. 1-62.
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