Asymmetric flux loops in active regions, II (original) (raw)

Abstract

We propose that magnetic flux loops in the subphotospheric layers of the Sun are seriously asymmetrical as a consequence of the drag force exerted on them because of the different rotational rate of the surrounding plasma. In numerical models of stationary slender flux loops in the plane parallel approximation we show that a serious tilt is both possible and probable. Observational facts (see van Driel-Gesztelyi and Petrovay, 1989; Paper I) strongly support the case for high asymmetry. The different stability of p and f spots may also be related to such an asymmetry.

The tilts are very sensitive to the rotational profile and to the magnetic field structure. Nevertheless the characteristic maximal tilts can be tentatively estimated to be 20° for thin flux tubes and 5° for thick tubes.

For two of the five observational consequences of such a tilt (described in detail in Paper I) order-of-magnitude estimates of the effects are given. The estimates are in reasonable accord with observations.

We also explore the possibilities of an inverse treatment of the problem whereby subphotospheric rotation and/or flux tube shapes can be inferred from observations of velocities of photospheric spot motions. In particular we demonstrate how analytic inverse solutions can be obtained in special cases.

Access this article

Log in via an institution

Subscribe and save

• Starting from 10 chapters or articles per month
• Access and download chapters and articles from more than 300k books and 2,500 journals
• Cancel anytime View plans

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

• Fisher, G. H., Chou, D.-Y., and McClymont, A.: 1988, ‘Emergence of Anchored Flux Tubes through the Convection Zone’, Univ. Hawaii preprint, to be published in an American Geophysical Union Monograph.
• Fletcher, L., Brown, J. C., and van Driel-Gesztelyi, L.: 1990, in preparation (Paper III).
• Foukal, P.: 1977, Astrophys. J. 218, 539.
  Google Scholar
• Howard, R.: 1974, Solar Phys. 39, 275.
  Google Scholar
• Meyer, F., Schmidt, H. U., Weiss, N. O.: 1977, Monthly Notices Roy. Astron. Soc. 179, 741.
  Google Scholar
• Meyer, F., Schmidt, H. U., Simon, G. V., and Weiss, N. O.: 1979, Astron. Astrophys. 76, 35.
  Google Scholar
• Moreno-Insertis, F.: 1986, Astron. Astrophys. 166, 291.
  Google Scholar
• Parker, E. N.: 1979, Cosmical Magnetic Fields, Clarendon Press, Oxford.
  Google Scholar
• van Ballegooijen, A. A.: 1982, Astron. Astrophys. 106, 43.
  Google Scholar
• van Driel-Gesztelyi, L. and Petrovay, K.: 1990, Solar Phys. 126, 285 (Paper I).
  Google Scholar

Download references

Author information

Authors and Affiliations

1. Department of Astronomy, Eötvös University, Kun B. tér 2, H-1083, Budapest, Hungary
   K. Petrovay & M. Marik
2. Department of Physics and Astronomy, University of Glasgow, G 12 8 QQ, Glasgow, Scotland
   J. C. Brown, L. Fletcher & G. Stewart
3. Heliophysical Observatory of the Hungarian Academy of Sciences, P.O. Box 30, H-4010, Debrecen, Hungary
   L. van Driel-Gesztelyi
4. Sterrenkundig Instituut, Postbus 80.000, NL-3508, Utrecht, TA, The Netherlands
   L. van Driel-Gesztelyi

Authors

1. K. Petrovay
2. J. C. Brown
3. L. van Driel-Gesztelyi
4. L. Fletcher
5. M. Marik
6. G. Stewart

Rights and permissions

About this article

Cite this article

Petrovay, K., Brown, J.C., van Driel-Gesztelyi, L. et al. Asymmetric flux loops in active regions, II.Sol Phys 127, 51–64 (1990). https://doi.org/10.1007/BF00158513

Download citation

• Received: 02 June 1989
• Revised: 23 January 1990
• Issue date: May 1990
• DOI: https://doi.org/10.1007/BF00158513

Keywords