Abstract
In this paper I discuss the importance of turbulence, rotation, penetration and shear for solar dynamos (both local and global). An understanding of these processes is vital for progress towards a self-consistent theory for the generation of solar magnetic activity. I discuss the difficulties for large-scale field generation and suggest that large-scale solar magnetic activity may be driven by dynamos that arise owing to instabilities, with these dynamos modified by the presence of turbulence.
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S. Boldyrev, F. Cattaneo, Magnetic-field generation in Kolmogorov turbulence. Phys. Rev. Lett. 92, 144501 (2004)
A. Brandenburg, The case for a distributed solar dynamo shaped by near-surface shear. Astrophys. J. 625, 539–547 (2005)
A. Brandenburg, D. Schmitt, Simulations of an alpha-effect due to magnetic buoyancy. Astron. Astrophys. 338, L55–L58 (1998)
A. Brandenburg, K. Subramanian, Astrophysical magnetic fields and nonlinear dynamo theory. Phys. Rep. 417, 1–209 (2005)
M.K. Browning, M.S. Miesch, A.S. Brun, J. Toomre, Dynamo action in the solar convection zone and tachocline: pumping and organization of toroidal fields. Astrophys. J. 648(2), L157–L160 (2006)
N.H. Brummell, F. Cattaneo, S.M. Tobias, The role of penetration in compressible dynamos (2008, in preparation)
F. Cattaneo, D.W. Hughes, Dynamo action in a rotating convective layer. J. Fluid Mech. 553, 401–418 (2006)
P. Charbonneau, K.B. MacGregor, Solar interface dynamos II. Linear kinematic models in spherical geometry. Astrophys. J. 486, 502 (1997)
K.S. Cline, N.H. Brummell, F. Cattaneo, Dynamo action driven by shear and magnetic buoyancy. Astrophys. J. 599, 1449–1468 (2003)
A.B. Iskakov, A.A. Schekochihin, S.C. Cowley, J.C. McWilliams, M.R.E. Proctor, Numerical demonstration of fluctuation dynamo at low magnetic Prandtl numbers. Phys. Rev. Lett. 98, 208501 (2007)
M. Ossendrijver, The solar dynamo. Astron. Astrophys. Rev. 11, 287 (2003)
E.N. Parker, Hydromagnetic dynamo models. Astrophys. J. 122, 293 (1955)
E.N. Parker, A solar dynamo surface wave at the interface between convection and nonuniform rotation. Astrophys. J. 408, 707 (1993)
M.R.E. Proctor, Effects of fluctuation on α−ω dynamo models. Month. Not. R. Astron. Soc.: Lett. 382, L39–L42 (2007)
E.A. Spiegel, N.O. Weiss, Magnetic activity and variations in solar luminosity. Nature 287, 616 (1980)
M. Steenbeck, F. Krause, K.-H. Rädler, Z. Naturforsch 21a, 364 (1966)
R.F. Stein, A. Nordlund, Solar surface magneto-convection and dynamo action, in SOLMAG 2002. Proceedings of the Magnetic Coupling of the Solar Atmosphere Euroconference and IAU Colloquium 188, 11–15 June 2002, Santorini, Greece, ed. by H. Sawaya-Lacoste. ESA SP-505, vol. 89 (ESA, Noordwijk, 2002), pp. 83–89
J.-C. Thelen, Non-linear α−ω-dynamos driven by magnetic buoyancy. Mon. Not. R. Astron. Soc. 315, 165–183 (2000)
S.M. Tobias, The solar tachocline: Formation, stability and its role in the solar dynamo, in Fluid Dynamics and Dynamos in Astrophysics and Geophysics, ed. by A.M. Soward, C.A. Jones, D.W. Hughes, N.O. Weiss (CRC, Boca Raton, 2005), pp. 193
S.M. Tobias, N.H. Brummell, T.L. Clune, J. Toomre, Transport and storage of magnetic field by overshooting turbulent compressible convection. Astrophys. J. 549, 1183–1203 (2001)
S.M. Tobias, N.O. Weiss, Stellar dynamos, in Mathematical Aspects of Natural Dynamos, ed. by E. Dormy, A.M. Soward (CRC, Boca Raton, 2007), pp. 281–312
S.M. Tobias, F. Cattaneo, Dynamo action in complex flows: the quick and the fast. J. Fluid Mech. 601, 101–122 (2008a)
S.M. Tobias, F. Cattaneo, On the limited role of spectra in dynamo theory. Phys. Rev. Lett. 101, 125003 (2008b)
S.M. Tobias, F. Cattaneo, N.H. Brummell, Dynamo action with penetration, rotation and shear. Astrophys. J. 685, 596 (2008)
S.I. Vainshtein, F. Cattaneo, Nonlinear restrictions on dynamo action. Astrophys. J. 393, 165–171 (1992)
E. Vishniac, A. Brandenuburg, An incoherent alpha-omega dynamo in accretion disks. Astrophys. J. 475, 263 (1997)
A. Vögler, M. Schüssler, A solar surface dynamo. Astron. Astrophys. 465, L43–L46 (2007)
N.O. Weiss, Thompson, Space Sci. Rev. (2008, this issue)
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Tobias, S.M. The Solar Dynamo: The Role of Penetration, Rotation and Shear on Convective Dynamos. Space Sci Rev 144, 77–86 (2009). https://doi.org/10.1007/s11214-008-9442-0
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DOI: https://doi.org/10.1007/s11214-008-9442-0