Abstract
We report on large-scale horizontal flows in the solar convection zone and their variability in time and space using a local-helioseismology technique known as ring-diagram analysis. By performing this analysis on a dense mosaic of individual regions on the solar disk, i.e., a ‘Dense-Pack’ sampling, and repeating the analysis periodically on several time scales, we are able to assess the variation of horizontal flows from day-to-day, week-to- week, and year-to-year. We find that although there are changes in the flows on all these time scales, there are also basic patterns that persist. On a daily time scale we observe that the flow is reduced in those areas which are occupied by large active regions. On somewhat longer time-scales we see bands of persistent fast and slow zonal flow that are identifiable as torsional oscillations. As we examine these bands during a series of years, we find that these bands migrate toward the equator as solar activity increases. Similarly, the latitudes at which the meridional flow reaches maximum follow these regions of fast zonal flow as they migrate equatorwards. These Dense-Pack samplings also reveal substantial differences in the zonal and meridional flow patterns in the northern and southern hemispheres.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Anderson, E. R., Duvall, T. L., Jr., and Jefferies, S. M.: 1990, Astrophys. J. 364, 699.
Basu, S., Antia, H. M., and Tripathy, S. C.: 1999, Astrophys. J. 512, 458.
Bogart, R. S., Sá, L. A. D., Duvall, T. L., Jr., Haber, D. A., Toomre, J., and F. Hill, F.: 1995, in J. T. Hoeksema, V. Domingo, B. Fleck, and B. Battrick (eds.), Proc. Fourth SOHO Workshop: Helioseismology, ESA SP-376, Vol. 2, p. 147.
Christensen-Dalsgaard, J., Gough, D. O., and Thompson, M. J.: 1989, Monthly Notices Royal Astron. Soc. 238, 481.
Christensen-Dalsgaard, J. et al.: 1996, Science 272, 1286.
Giles, P. M., Duvall, T. L., Jr., Scherrer, P. H., and Bogart, R. S.: 1997, Nature 390, 52.
Giles, P. M., Duvall, T. L., Jr., and Scherrer, P. H.: 1998, in S. Korzennik and A. Wilson (eds.), Structure and Dynamics of the Interior of the Sun and Sun-like Stars, ESA SP-418, Vol. 2, p. 775.
Gonzalez-Hernandez, I. E., Patrón, J., Bogart, R. S., and the SOI Ring Diagrams Team: 1998, in S. Korzennik and A. Wilson (eds.), Structure and Dynamics of the Interior of the Sun and Sun-like Stars, ESA SP-418, Vol. 12, p. 781.
Gonzalez-Hernandez, I. E., Patrón, J., Bogart, R. S., and the SOI Ring Diagrams Team: 1999, Astrophys. J. 510, L153.
Haber, D. A., Toomre, J., Hill, F., and Gough, D.: 1995a, in R. K. Ulrich, E. J. Rhodes, Jr., and W. Däppen (eds.), GONG’ 94: Helio-and Astero-Seismology from the Earth and Space, p. 272.
Haber, D. A., Toomre, J., Hill, F., and Gough, D.: 1995b, in J. T. Hoeksema, V. Domingo, B. Fleck, and B. Battrick (eds.), Proc. Fourth SOHO Workshop: Helioseismology, ESA SP-376, Vol. 2, p. 141.
Haber, D. A., Hindman, B. W., Toomre, J., Bogart, R. S., Schou, J., and Hill, F.: 1998, in S. Korzennik and A. Wilson (eds.), Structure and Dynamics of the Interior of the Sun and Sun-like Stars, ESA SP-418, Vol. 2, p. 791.
Hill, F.: 1988, Astrophys. J. 333, 996.
Howard, R. and LaBonte, B. J.: 1980, Astrophys. J. 239, L33.
Howe, R., Komm, R., and Hill, F.: 2000, Solar Phys. 192, 429 (this issue).
Kosovichev, A. G. and Schou, J.: 1997, Astrophys. J. 482, L207.
Patrón, J., Hill, F., Rhodes, E. J., Jr., Kozennik, S. G., and Cacciani, A.: 1995, Astrophys. J. 455, 746.
Scherrer, P. H. et al.: 1995, Solar Phys. 162, 129.
Schou, J.: 1999, Astrophys. J. 523, L181.
Schou, J. and Bogart, R. S.: 1998, Astrophys. J. 504, L131.
Schou, J. et al.: 1998a, in F.-L. Deubner, J. Christensen-Dalsgaard, and D. Kurtz (eds.), Proc. IAU Symp. 185, p. 141.
Schou, J. et al.: 1998b, Astrophys. J. 505, 390.
Snodgrass, H. B.: 1984, Solar Phys. 94, 13.
Thompson, M. J. et al.: 1996, Science 272, 1300.
Toomre, J., Christensen-Dalsgaard, J., Howe, R., Larsen, R. M., Schou, J., and Thompson, M. J.,: 2000, Solar Phys. 192, 437 (this issue).
Ulrich, R.: 1998, in S. Korzennik and A. Wilson (eds.), Structure and Dynamics of the Interior of the Sun and Sun-like Stars, ESA SP-418, Vol. 2, p. 851.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2000 Springer Science+Business Media Dordrecht
About this chapter
Cite this chapter
Haber, D.A., Hindman, B.W., Toomre, J., Bogart, R.S., Thompson, M.J., Hill, F. (2000). Solar Shear Flows Deduced From Helioseismic Dense-Pack Samplings of Ring Diagrams. In: Duvall, T.L., Harvey, J.W., Kosovichev, A.G., Švestka, Z. (eds) Helioseismic Diagnostics of Solar Convection and Activity. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-4377-6_21
Download citation
DOI: https://doi.org/10.1007/978-94-011-4377-6_21
Publisher Name: Springer, Dordrecht
Print ISBN: 978-94-010-5882-7
Online ISBN: 978-94-011-4377-6
eBook Packages: Springer Book Archive