### Citations

64 | Astrophysical magnetic fields and nonlinear dynamo theory,
- Brandenburg, Subramanian
- 2005
(Show Context)
Citation Context ...ociated results are part of a growing body of work that reflects how magnetic helicity has emerged as a useful tool for understanding the operation and nonlinear evolution of large-scale dynamos (see =-=[3]-=- for a review). It is important to distinguish practical modeling of planetary and stellar dynamos, where the immediate aim is to specifically reproduce observations, from idealized studies of simple ... |

53 |
Strong MHD helical turbulence and nonlinear dynamo effect.
- Pouquet, Frisch, et al.
- 1976
(Show Context)
Citation Context ... that systematically amplify or sustain fields on spatial or temporal scales larger than those of the fluctuations involve a spatial or spectral transfer of magnetic helicity. (first apparent in Ref. =-=[2]-=- for type 2 dynamos.) Examples of steady-state vs. time dependent dynamos in the presence and absence of boundary terms and the influence on dynamo saturation will be discussed. For the simplest close... |

23 |
The case for a distributed solar dynamo shaped by near-surface shear, Astrophys
- Brandenburg
(Show Context)
Citation Context ... the velocity and torques delivered by both motors are recorded during the experiments, (ii) the radial and azimuthal components of the sodium velocity are measured by ultrasonic Doppler velocimetry (=-=[2]-=-), (iii) differences in electrical potential are measured at the surface of the external sphere, (iv) the induced magnetic field is measured outside the external sphere (vi) the dynamical pressure is ... |

15 | Magnetic helicity conservation and astrophysical dynamos, Astrophys
- Vishniac, Cho
(Show Context)
Citation Context ... determinations for incompressible fluids and magnetofluids, J. Plasma Physics, 64, 371 – 377. [3] X Shan, et al. Phys. Rev. 44A., 6800 (1991); Plasma Phys. and Contr. Fusion 35, 619 and 1019 (1993). =-=[4]-=- Z. Yoshida 1992 Eigenfunction expansions associated with the curl derivatives in cylindrical geometries: Completeness of ChandrasekharKendall eigenfunctions J. Math. Phys., 33, 1252 – 1271. [5] P. D.... |

5 |
2004, Global-Scale Turbulent Convection and Magnetic Dynamo Action in the Solar Envelope
- Brun, Miesch, et al.
(Show Context)
Citation Context ...uite well [6]. However, modeling the relative shift of the small-scale magnetic peak with respect to the small scale velocity peak at early times requires at least a three scale helical dynamo theory =-=[7]-=-. The three scale approach does show that the small-scale helical magnetic energy first saturates at very small scales, but then successively saturates at larger values at larger scales, eventually be... |

3 |
2006. Galactic dynamo and helicity losses through fountain Astron. Astrophys
- Shukurov, Sokolo, et al.
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Citation Context ...sometimes exhibits a multiple jet structure, and sometimes has a simple radial structure. Factors aecting multiple jet formation will be considered. We compare our results with the inertial scaling, =-=[2, 3]-=-, developed to study rapidly rotating convection, which predicts that Ûc RQ 2=5(EP )1=5, where RQ is thesux Rayleigh number, RQ = R(Nu 1), and E is the Ekman number, = d2, d being the gap betwee... |

2 |
2004. Nonlinear current helicity in turbulent dynamos and alpha
- Subramanian, Brandenburg
(Show Context)
Citation Context ...uctuating displacement ). 3. Results We outline the equations for the contravariant and covariant vectorselds that emerge from the governing equations of the full rotating MHD system (as reviewed in =-=[5]-=-). Holm [6] calls them the Generalised Lagrangian Mean (GLM) equations. We consider their expansions up to O(j j2) extending on the earlier developments of [3], [4] and [6]. Holm has also proposed an... |

2 |
2006. arXiv: astro-ph/0509392, Magnetic helicity density and its in inhomogeneous turbulence
- Subramanian, Brandenburg
(Show Context)
Citation Context .... Comp. Phys. 215, 1–5. [5] A. Fournier, G. Beylkin and V. Cheruvu 2005. Multiresolution adaptive space refinement in geophysical fluid dynamics simulation, Lecture Notes Comp. Sci. Eng. 41, 161–170. =-=[6]-=- A. Fournier, M.A. Taylor and J.J. Tribbia 2004. The spectral element atmosphere model (SEAM): Highresolution parallel computation and localized resolution of regional dynamics, Mon. Wea. Rev. 132, 72... |

2 |
McWilliams 2005. Onset of small scale dynamo at small magnetic Prandtl numbers, Astrophys
- Schekochihin, Haugen, et al.
(Show Context)
Citation Context ...trinsically locally low-order w.r.t. the X~̀ size h~̀. However, a few AMR codes are locally high-order w.r.t. a parameter p~̀ in each X~̀; these include adaptive spectral-element methods (SEMs, e.g., =-=[6, 7, 8]-=- and op. cit. therein). The combined h-p analyses built into SEM make it very effective for complicated flows [5, 6, 7, 8]. Using SEM combined with LSI, we can quantitatively model and analyze many im... |

2 |
Sarson 2002. The eect of hyperdiusivity on turbulent dynamos with helicity
- Brandenburg, R
(Show Context)
Citation Context ...cale field formation paradigm is this: First, a type 2 velocity driven helical dynamo amplifies fields of large enough scale that they buoyantly rise and supply magnetic helicity to the to the corona =-=[9, 10]-=- without being shredding by turbulent diffusion. Once in the corona, continued footpoint motions can further twist the field and inject more magnetic helicity. The loops respond by rising or opening t... |

2 | 2006. arXiv: astro-ph/0412666, Hydrodynamic and hydromagnetic energy spectra from large eddy simulations - Haugen, Brandenburg |

1 |
The Inverse Cascade and Nonlinear Alpha-Effect
- ApJ
(Show Context)
Citation Context ...ed that insights gained from the latter can eventually be incorporated into the former. In this context, idealized type 2 MHD dynamo simulations of α2 dynamos in periodic boxes by several groups e.g. =-=[4, 5]-=- have shown that when MHD turbulence is forced with sufficient kinetic helicity, the saturated magnetic energy spectrum evolves from having a single peak below the forcing scale to become doubly peake... |

1 |
344, 707, Understanding helical magnetic dynamo spectra with a nonlinear four-scale theory
- Blackman
(Show Context)
Citation Context ...uite well [6]. However, modeling the relative shift of the small-scale magnetic peak with respect to the small scale velocity peak at early times requires at least a three scale helical dynamo theory =-=[7]-=-. The three scale approach does show that the small-scale helical magnetic energy first saturates at very small scales, but then successively saturates at larger values at larger scales, eventually be... |

1 | Extracting rotational energy in supernova progenitors: Transient Poynting flux growth vs. turbulent dissipation
- Blackman, Nordhaus, et al.
- 2006
(Show Context)
Citation Context ... corona. Note that we observe the exterior field, not the interior field for all astrophysical rotators except our Galaxy. Finally, I will briefly mention some work on interface dynamos in supernovae =-=[11]-=-. For protosupernovae unlike the sun, the backreaction on the differential rotation is important in limiting the lifetime of the dynamo. These supernovae interface dynamos are explosive, not steady, a... |