No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
The full text of this article is not currently available.
The appearance, motion, and disappearance of three-dimensional magnetic null points
1. E. Priest and T. Forbes, Magnetic Reconnection: MHD Theory and Applications ( Cambridge University Press, Cambridge, 2000).
2.Reconnection of Magnetic Fields: Magnetohydrodynamics and Collisionless Theory and Observations, edited by J. Birn and E. R. Priest ( Cambridge University Press, Cambridge, 2007).
5. S. W. H. Cowley, “ A qualitative study of the reconnection between the Earth's magnetic field and an interplanetary field of arbitrary orientation,” Radio Sci. 8, 903, doi:10.1029/RS008i011p00903 (1973).
6. S. Fukao, M. Ugai, and T. Tsuda, “ Topological study of magnetic field near a neutral point,” RISRJ 29, 133 (1975).
7. J. M. Greene, “ Geometrical properties of three-dimensional reconnecting magnetic fields with nulls,” J. Geophys. Res. 93, 8583, doi:10.1029/JA093iA08p08583 (1988).
8. Y.-T. Lau and J. M. Finn, “ Three-dimensional kinematic reconnection in the presence of field nulls and closed field lines,” Astrophys. J. 350, 672 (1990).
9. C. E. Parnell, J. M. Smith, T. Neukirch, and E. R. Priest, “ The structure of three-dimensional magnetic neutral points,” Phys. Plasmas 3, 759 (1996).
10. C. J. Xiao, X. G. Wang, Z. Y. Pu, H. Zhao, J. X. Wang, Z. W. Ma, S. Y. Fu, M. G. Kivelson, Z. X. Liu, Q. G. Zong, K. H. Glassmeier, A. Balogh, A. Korth, H. Reme, and C. P. Escoubet, “ In situ evidence for the structure of the magnetic null in a 3D reconnection event in the Earth's magnetotail,” Nat. Phys. 2, 478 (2006).
11. C. J. Xiao, X. G. Wang, Z. Y. Pu, Z. W. Ma, H. Zhao, G. P. Zhou, J. X. Wang, M. G. Kivelson, S. Y. Fu, Z. X. Liu, Q. G. Zong, M. W. Dunlop, K.-H. Glassmeier, E. Lucek, H. Reme, I. Dandouras, and C. P. Escoubet, “ Satellite observations of separator-line geometry of three-dimensional magnetic reconnection,” Nat. Phys. 3, 609 (2007).
12. J.-S. He, C.-Y. Tu, H. Tian, C.-J. Xiao, X.-G. Wang, Z.-Y. Pu, Z.-W. Ma, M. W. Dunlop, H. Zhao, G.-P. Zhou, J.-X. Wang, S.-Y. Fu, Z.-X. Liu, Q.-G. Zong, K.-H. Glassmeier, H. Reme, I. Dandouras, and C. P. Escoubet, “ A magnetic null geometry reconstructed from Cluster spacecraft observations,” J. Geophys. Res. 113, A05205, doi:10.1029/2007JA012609 (2008).
13. D. E. Wendel and M. L. Adrian, “ Current structure and nonideal behavior at magnetic null points in the turbulent magnetosheath,” J. Geophys. Res. 118, 1571, doi:10.1002/jgra.50234 (2013).
14. R. Guo, Z. Pu, C. Xiao, X. Wang, S. Fu, L. Xie, Q. Zong, J. He, Z. Yao, J. Zhong, and J. Li, “ Separator reconnection with antiparallel/component features observed in magnetotail plasmas,” J. Geophys. Res. 118, 6116, doi:10.1002/jgra.50569 (2013).
15. H. S. Fu, A. Vaivads, Y. V. Khotyaintsev, V. Olshevsky, M. André, J. B. Cao, S. Y. Huang, A. Retinò, and G. Lapenta, “ How to find magnetic nulls and reconstruct field topology with MMS data?,” J. Geophys. Res. 120, 3758, doi:10.1002/2015JA021082 (2015).
18. G. Aulanier, E. E. DeLuca, S. K. Antiochos, R. A. McMullen, and L. Golub, “ The topology and evolution of the Bastille day flare,” Astrophys. J. 540, 1126 (2000).
19. H. Zhao, J.-X. Wang, J. Zhang, C.-J. Xiao, and H.-M. Wang, “ Determination of the topology skeleton of magnetic fields in a solar active region,” Chin. J. Astron. Astrophys. 8, 133 (2008).
21. M. S. Freed, D. W. Longcope, and D. E. McKenzie, “ Three-year global survey of coronal null points from potential-field-source-surface (PFSS) modeling and solar dynamics observatory (SDO) observations,” Sol. Phys. 290, 467 (2015).
24. P. Démoulin, J. C. Hénoux, and C. H. Mandrini, “ Are magnetic null points important in solar flares?,” Astron. Astrophys. 285, 1023 (1994).
25. G. Barnes, “ On the relationship between coronal magnetic null points and solar eruptive events,” Astrophys. J. Lett. 670, L53 (2007).
28. S. Servidio, W. H. Matthaeus, M. A. Shay, P. A. Cassak, and P. Dmitruk, “ Magnetic reconnection in two-dimensional magnetohydrodynamic turbulence,” Phys. Rev. Lett. 102, 115003 (2009).
29. S. Servidio, W. H. Matthaeus, M. A. Shay, P. Dmitruk, P. A. Cassak, and M. Wan, “ Statistics of magnetic reconnection in two-dimensional magnetohydrodynamic turbulence,” Phys. Plasmas 17, 032315 (2010).
31. C. E. Parnell, R. C. Maclean, and A. L. Haynes, “ The detection of numerous magnetic separators in a three-dimensional magnetohydrodynamic model of solar emerging flux,” Astrophys. J. 725, L214 (2010).
32. E. R. Priest, G. Hornig, and D. I. Pontin, “ On the nature of three-dimensional magnetic reconnection,” J. Geophys. Res. 108, 1285, doi:10.1029/2002JA009812 (2003).
37. C. E. Parnell, A. L. Haynes, and K. Galsgaard, “ Structure of magnetic separators and separator reconnection,” J. Geophys. Res. 115, 2102, doi:10.1029/2009JA014557 (2010).
39. K. Schindler, M. Hesse, and J. Birn, “ General magnetic reconnection, parallel electric fields, and helicity,” J. Geophys. Res. 93, 5547, doi:10.1029/JA093iA06p05547 (1988).
40. E. R. Priest and T. G. Forbes, “ Magnetic flipping—reconnection in three dimensions without null points,” J. Geophys. Res. 97, 1521, doi:10.1029/91JA02435 (1992).
42. M. Janvier, G. Aulanier, E. Pariat, and P. Démoulin, “ The standard flare model in three dimensions. III. Slip-running reconnection properties,” Astron. Astrophys. 555, A77 (2013).
43. T. G. Forbes, E. W. Hones, S. J. Bame, J. R. Asbridge, G. Paschmann, N. Sckopke, and C. T. Russell, “ Evidence for the tailward retreat of a magnetic neutral line in the magnetotail during substorm recovery,” Geophys. Res. Lett. 8, 261, doi:10.1029/GL008i003p00261 (1981).
44. H. Hasegawa, A. Retinò, A. Vaivads, Y. Khotyaintsev, R. Nakamura, T. Takada, Y. Miyashita, H. Rème, and E. A. Lucek, “ Retreat and reformation of X-line during quasi-continuous tailward-of-the-cusp reconnection under northward IMF,” Geophys. Res. Lett. 35, L15104, doi:10.1029/2008GL034767 (2008).
45. M. Oka, T.-D. Phan, J. P. Eastwood, V. Angelopoulos, N. A. Murphy, M. Øieroset, Y. Miyashita, M. Fujimoto, J. McFadden, and D. Larson, “ Magnetic reconnection X-line retreat associated with dipolarization of the Earth's magnetosphere,” Geophys. Res. Lett. 38, 20105, doi:10.1029/2011GL049350 (2011).
46. X. Cao, Z. Y. Pu, A. M. Du, V. M. Mishin, X. G. Wang, C. J. Xiao, T. L. Zhang, V. Angelopoulos, J. P. McFadden, and K. H. Glassmeier, “ On the retreat of near-Earth neutral line during substorm expansion phase: A THEMIS case study during the 9 January 2008 substorm,” Ann. Geophys. 30, 143 (2012).
47. F. D. Wilder, S. Eriksson, K. J. Trattner, P. A. Cassak, S. A. Fuselier, and B. Lybekk, “ Observation of a retreating x line and magnetic islands poleward of the cusp during northward interplanetary magnetic field conditions,” J. Geophys. Res. 119, 9643, doi:10.1002/2014JA020453 (2014).
48. M. Swisdak, B. N. Rogers, J. F. Drake, and M. A. Shay, “ Diamagnetic suppression of component magnetic reconnection at the magnetopause,” J. Geophys. Res. 108, 1218, doi:10.1029/2002JA009726 (2003).
49. T. D. Phan, G. Paschmann, J. T. Gosling, M. Oieroset, M. Fujimoto, J. F. Drake, and V. Angelopoulos, “ The dependence of magnetic reconnection on plasma β and magnetic shear: Evidence from magnetopause observations,” Geophys. Res. Lett. 40, 11, doi:10.1029/2012GL054528 (2013).
52. M. Inomoto, S. P. Gerhardt, M. Yamada, H. Ji, E. Belova, A. Kuritsyn, and Y. Ren, “ Coupling between global geometry and the local Hall effect leading to reconnection-layer symmetry breaking,” Phys. Rev. Lett. 97, 135002 (2006).
53. J. Yoo, M. Yamada, H. Ji, J. Jara-Almonte, C. E. Myers, and L.-J. Chen, “ Laboratory study of magnetic reconnection with a density asymmetry across the current sheet,” Phys. Rev. Lett. 113, 095002 (2014).
54. N. A. Murphy and C. R. Sovinec, “ Global axisymmetric simulations of two-fluid reconnection in an experimentally relevant geometry,” Phys. Plasmas 15, 042313 (2008).
57. S. L. Savage, D. E. McKenzie, K. K. Reeves, T. G. Forbes, and D. W. Longcope, “ Reconnection outflows and current sheet observed with Hinode/XRT in the 2008 April 9 ‘Cartwheel CME’ flare,” Astrophys. J. 722, 329 (2010).
58. P. A. Cassak and M. A. Shay, “ Scaling of asymmetric magnetic reconnection: General theory and collisional simulations,” Phys. Plasmas 14, 102114 (2007).
59. P. A. Cassak and M. A. Shay, “ Scaling of asymmetric Hall magnetic reconnection,” Geophys. Res. Lett. 35, 19102, doi:10.1029/2008GL035268 (2008).
60. P. A. Cassak and M. A. Shay, “ Structure of the dissipation region in fluid simulations of asymmetric magnetic reconnection,” Phys. Plasmas 16, 055704 (2009).
61. N. A. Murphy, C. R. Sovinec, and P. A. Cassak, “ Magnetic reconnection with asymmetry in the outflow direction,” J. Geophys. Res. 115, 9206, doi:10.1029/2009JA015183 (2010).
62. N. A. Murphy, “ Resistive magnetohydrodynamic simulations of X-line retreat during magnetic reconnection,” Phys. Plasmas 17, 112310 (2010).
65. N. A. Murphy, M. P. Miralles, C. L. Pope, J. C. Raymond, H. D. Winter, K. K. Reeves, D. B. Seaton, A. A. van Ballegooijen, and J. Lin, “ Asymmetric magnetic reconnection in solar flare and coronal mass ejection current sheets,” Astrophys. J. 751, 56 (2012).
66. G. L. Siscoe, G. M. Erickson, B. U. Sonnerup, N. C. Maynard, J. A. Schoendorf, K. D. Siebert, D. R. Weimer, W. W. White, and G. R. Wilson, “ Flow-through magnetic reconnection,” Geophys. Res. Lett. 29, 4-1, doi:10.1029/2001GL013536 (2002).
67. N. C. Maynard, C. J. Farrugia, W. J. Burke, D. M. Ober, F. S. Mozer, H. Rème, M. Dunlop, and K. D. Siebert, “ Cluster observations of the dusk flank magnetopause near the sash: Ion dynamics and flow-through reconnection,” J. Geophys. Res. 117, A10201, doi:10.1029/2012JA017703 (2012).
70. T. Klein and T. Ertl, “ Scale-space tracking of critical points in 3d vector fields,” in Topology-based Methods in Visualization, Mathematics and Visualization, edited by H. Hauser, H. Hagen, and H. Theisel ( Springer, Berlin, Heidelberg, 2007) pp. 35–49.
72. R. M. Kulsrud, Plasma Physics for Astrophysics ( Princeton University Press, Princeton, NJ, 2005).
74. K. Deimling, Nonlinear Functional Analysis ( Springer-Verlag, New York, 1985).
79. A. L. Haynes and C. E. Parnell, “ A trilinear method for finding null points in a three-dimensional vector space,” Phys. Plasmas 14, 082107 (2007).
86.Null points are also known as neutral points, fixed points, stationary points, equilibrium points, critical points, singular points, and singularities. Separators are also known as saddle connectors and separation/attachment lines. Separatrix surfaces are also known as fans and separation surfaces.
Article metrics loading...
While theoretical models and simulations of magnetic reconnection often assume symmetry such that the magnetic null point when present is co-located with a flow stagnation point, the introduction of asymmetry typically leads to non-ideal flows across the null point. To understand this behavior, we present exact expressions for the motion of three-dimensional linear null points. The most general expression shows that linear null points move in the direction along which the magnetic field and its time derivative are antiparallel. Null point motion in resistive magnetohydrodynamics results from advection by the bulk plasma flow and resistive diffusion of the magnetic field, which allows non-ideal flows across topological boundaries. Null point motion is described intrinsically by parameters evaluated locally; however, global dynamics help set the local conditions at the null point. During a bifurcation of a degenerate null point into a null-null pair or the reverse, the instantaneous velocity of separation or convergence of the null-null pair will typically be infinite along the null space of the Jacobian matrix of the magnetic field, but with finite components in the directions orthogonal to the null space. Not all bifurcating null-null pairs are connected by a separator. Furthermore, except under special circumstances, there will not exist a straight line separator connecting a bifurcating null-null pair. The motion of separators cannot be described using solely local parameters because the identification of a particular field line as a separator may change as a result of non-ideal behavior elsewhere along the field line.
Full text loading...
Most read this month