Results 141 to 150 of about 1,036 (175)
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Magnetoconvection and the solar dynamo
Journal of Astrophysics and Astronomy, 2000AbstractWe review current understanding of the interaction of magnetic fields with convective motions in stellar convection zones. Among the most exciting recent results is the discovery that magnetic fields need not primarily be confined to the stable layer below the convection zone; numerical simulations have shown that surprisingly, strong magnetic ...
Å. Nordlund +2 more
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Space Science Reviews, 2009
Observations relevant to current models of the solar dynamo are presented, with emphasis on the history of solar magnetic activity and on the location and nature of the solar tachocline. The problems encountered when direct numerical simulation is used to analyse the solar cycle are discussed, and recent progress is reviewed.
Chris A. Jones +2 more
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Observations relevant to current models of the solar dynamo are presented, with emphasis on the history of solar magnetic activity and on the location and nature of the solar tachocline. The problems encountered when direct numerical simulation is used to analyse the solar cycle are discussed, and recent progress is reviewed.
Chris A. Jones +2 more
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Solar Physics, 1985
The basic features of the solar activity mechanism are explained in terms of the dynamo theory of mean magnetic fields. The field generation sources are the differential rotation and the mean helicity of turbulent motions in the convective zone. A nonlinear effect of the magnetic field upon the mean helicity results in stabilizing the amplitude of the ...
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The basic features of the solar activity mechanism are explained in terms of the dynamo theory of mean magnetic fields. The field generation sources are the differential rotation and the mean helicity of turbulent motions in the convective zone. A nonlinear effect of the magnetic field upon the mean helicity results in stabilizing the amplitude of the ...
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1994
I discuss the current status of mean field dynamo theory as it is applied to the solar cycle. The restrictions of the theory are pointed out, in particular the First Order Smoothing Approximation and the large fluctuations in the magnetic field superposed on the mean field; potential ways out are indicated.
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I discuss the current status of mean field dynamo theory as it is applied to the solar cycle. The restrictions of the theory are pointed out, in particular the First Order Smoothing Approximation and the large fluctuations in the magnetic field superposed on the mean field; potential ways out are indicated.
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The solar dynamo wave in Parker's migratory dynamo
Astronomical & Astrophysical Transactions, 1999Abstract A kinematic αω-dynamo model of magnetic field generation in a thin convection shell with a non-uniform but sign-constant helicity profile for large dynamo numbers is considered in the framework of Parker's migratory dynamo. We obtained an asymptotic solution of equations governing the magnetic field with the form of an anharmonic travelling ...
K. M. Kuzanyan, D. Sokoloff
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2020
Abstract The solar dynamo is the action of flows inside the Sun to maintain its magnetic field against Ohmic decay. On small scales the magnetic field is seen at the solar surface as a ubiquitous “salt-and-pepper” disorganized field that may be generated directly by the turbulent convection.
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Abstract The solar dynamo is the action of flows inside the Sun to maintain its magnetic field against Ohmic decay. On small scales the magnetic field is seen at the solar surface as a ubiquitous “salt-and-pepper” disorganized field that may be generated directly by the turbulent convection.
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Astronomy and Astrophysics Review, 2003
The solar dynamo continues to pose a challenge to observers and theoreticians. Observations of the solar surface reveal a magnetic field with a complex, hierarchical structure consisting of widely different scales. Systematic features such as the solar cycle, the butterfly diagram, and Hale's polarity laws point to the existence of a deep-rooted large ...
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The solar dynamo continues to pose a challenge to observers and theoreticians. Observations of the solar surface reveal a magnetic field with a complex, hierarchical structure consisting of widely different scales. Systematic features such as the solar cycle, the butterfly diagram, and Hale's polarity laws point to the existence of a deep-rooted large ...
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1998
The solar dynamo is the process by which the Sun's magnetic field is generated through the interaction of the field with convection and rotation. In this, it is kin to planetary dynamos and other stellar dynamos. Although the precise mechanism by which the Sun generates its field remains poorly understood in spite of decades of theoretical and ...
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The solar dynamo is the process by which the Sun's magnetic field is generated through the interaction of the field with convection and rotation. In this, it is kin to planetary dynamos and other stellar dynamos. Although the precise mechanism by which the Sun generates its field remains poorly understood in spite of decades of theoretical and ...
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On the non-symmetric solar dynamo
Solar Physics, 1981The external field of the solar magnetohydrodynamic dynamo is expressed in terms of spherical harmonics and in powers of 1/r. The non-symmetric dynamo is stabilized by a φ -dependent rotational oscillation which interacts with the magnetic field, thus compensating for Ohmic loss.
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AIP Conference Proceedings, 2004
The Sun, solar and later spectral type stars show cyclical magnetic activity that manifests itself through the presence of spots on their surfaces. The characteristics of this activity show broad variations both in spot periods, which range from a few to more than 20 years, and spot surface coverages, which range from 0.002 for the Sun to more than 0.5
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The Sun, solar and later spectral type stars show cyclical magnetic activity that manifests itself through the presence of spots on their surfaces. The characteristics of this activity show broad variations both in spot periods, which range from a few to more than 20 years, and spot surface coverages, which range from 0.002 for the Sun to more than 0.5
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