Search for Giant Cells in the Solar Convection Zone

AbstractIn addition to the well-known granulation and supergranulation of the solar convection zone (the “SCZ”), the presence of so-called “giant cells” has been postulated. These are supposed span the entire thickness of the SCZ and to stretch from pole to pole in a sequence of elongated cells like a “cartridge belt” or a bunch of “bananas” strung uniformly round the Sun. Conclusive evidence for the existence of such giant cells is still lacking, despite strenuous observational efforts to find them. After analyses of sunspot motion, Ribes and others believe that convective motions near the solar surface occurs in a pattern that is the antithesis of the cartridge belt: a system of “toroidal” or “doughnut” cells, girdling the Sun in a sequence that extends from one pole to the other. Galloway, Jones and Roberts have recently tried to meet the resulting theoretical challenge, with the mixed success reported in this paper.

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Search for Giant Cells in the Solar Convection Zone

Symposium - International Astronomical Union ◽

10.1017/s0074180900067280 ◽

1980 ◽

Vol 91 ◽

pp. 21-23 ◽

Cited By ~ 1

Author(s):

B. J. Labonte ◽

R. Howard

Keyword(s):

Large Scale ◽

Convection Zone ◽

Solar Rotation ◽

Longitudinal Velocity ◽

Giant Cells ◽

Solar Convection Zone ◽

Solar Convection ◽

Mount Wilson Observatory ◽

Entire Dataset ◽

Full Disk

The Mount Wilson Observatory has obtained daily full disk digital magnetograms of the Sun since 1966, with 12 to 17 arcsecond resolution. As each magnetogram is taken, the position of the Doppler line shift compensator is also recorded, thus giving a full disk map of the longitudinal velocity. This entire dataset is currently being rereduced on a uniform basis (Howard et al., 1980), and daily arrays of residual velocities are being formed by removing large scale patterns, e.g., Earth's motions, solar rotation, limbshift. Data from the years 1972 through 1978 are used here.

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Can short time delays influence the variability of the solar cycle?

Proceedings of the International Astronomical Union ◽

10.1017/s1743921311017716 ◽

2010 ◽

Vol 6 (S271) ◽

pp. 288-296

Author(s):

Laurène Jouve ◽

Michael R. E. Proctor ◽

Geoffroy Lesur

Keyword(s):

Solar Cycle ◽

Convection Zone ◽

Mean Field ◽

Period Doubling ◽

Temporal Modulation ◽

Solar Convection Zone ◽

Flux Tubes ◽

Solar Convection ◽

Short Time ◽

Period Doubling Bifurcations

AbstractWe present the effects of introducing results of 3D MHD simulations of buoyant magnetic fields in the solar convection zone in 2D mean-field Babcock-Leighton models. In particular, we take into account the time delay introduced by the rise time of the toroidal structures from the base of the convection zone to the solar surface. We find that the delays produce large temporal modulation of the cycle amplitude even when strong and thus rapidly rising flux tubes are considered. The study of a reduced model reveals that aperiodic modulations of the solar cycle appear after a sequence of period doubling bifurcations typical of non-linear systems. We also discuss the memory of such systems and the conclusions which may be drawn concerning the actual solar cycle variability.

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