Possible dipole tilt dependence of dayside magnetopause reconnection

2003 ◽  
Vol 30 (18) ◽  
Author(s):  
C. T. Russell ◽  
Y. L. Wang ◽  
J. Raeder
2021 ◽  
Author(s):  
Yann Pfau-Kempf ◽  
Minna Palmroth ◽  
Andreas Johlander ◽  
Lucile Turc ◽  
Markku Alho ◽  
...  

<p>Dayside magnetic reconnection at the magnetopause, which is a major driver of space weather, is studied for the first time in a three-dimensional (3D) realistic setup using the Vlasiator hybrid-Vlasov kinetic model. A noon–midnight meridional plane simulation is extended in the dawn–dusk direction to cover 7 Earth radii. The southward interplanetary magnetic field causes magnetic reconnection to occur at the subsolar magnetopause. Perturbations arising from kinetic instabilities in the magnetosheath appear to modulate the reconnection. Its characteristics are consistent with multiple, bursty, and patchy magnetopause reconnection. It is shown that the kinetic behavior of the plasma, as simulated by the model, has consequences on the applicability of methods such as the four-field junction to identify and analyse magnetic reconnection in 3D kinetic simulations.</p>


2006 ◽  
Vol 24 (3) ◽  
pp. 961-972 ◽  
Author(s):  
S. K. Morley ◽  
M. Lockwood

Abstract. Using a numerical implementation of the cowlock92 model of flow excitation in the magnetosphere-ionosphere (MI) system, we show that both an expanding (on a ~12-min timescale) and a quasi-instantaneous response in ionospheric convection to the onset of magnetopause reconnection can be accommodated by the Cowley-Lockwood conceptual framework. This model has a key feature of time dependence, necessarily considering the history of the coupled MI system. We show that a residual flow, driven by prior magnetopause reconnection, can produce a quasi-instantaneous global ionospheric convection response; perturbations from an equilibrium state may also be present from tail reconnection, which will superpose constructively to give a similar effect. On the other hand, when the MI system is relatively free of pre-existing flow, we can most clearly see the expanding nature of the response. As the open-closed field line boundary will frequently be in motion from such prior reconnection (both at the dayside magnetopause and in the cross-tail current sheet), it is expected that there will usually be some level of combined response to dayside reconnection.


2019 ◽  
Vol 124 (11) ◽  
pp. 8778-8787
Author(s):  
D. Koga ◽  
W. D. Gonzalez ◽  
V. M. Souza ◽  
F. R. Cardoso ◽  
C. Wang ◽  
...  

2017 ◽  
Vol 122 (5) ◽  
pp. 5105-5113 ◽  
Author(s):  
J. M. Broll ◽  
S. A. Fuselier ◽  
K. J. Trattner

2016 ◽  
Vol 34 (11) ◽  
pp. 943-959 ◽  
Author(s):  
Yann Pfau-Kempf ◽  
Heli Hietala ◽  
Steve E. Milan ◽  
Liisa Juusola ◽  
Sanni Hoilijoki ◽  
...  

Abstract. We present a scenario resulting in time-dependent behaviour of the bow shock and transient, local ion reflection under unchanging solar wind conditions. Dayside magnetopause reconnection produces flux transfer events driving fast-mode wave fronts in the magnetosheath. These fronts push out the bow shock surface due to their increased downstream pressure. The resulting bow shock deformations lead to a configuration favourable to localized ion reflection and thus the formation of transient, travelling foreshock-like field-aligned ion beams. This is identified in two-dimensional global magnetospheric hybrid-Vlasov simulations of the Earth's magnetosphere performed using the Vlasiator model (http://vlasiator.fmi.fi). We also present observational data showing the occurrence of dayside reconnection and flux transfer events at the same time as Geotail observations of transient foreshock-like field-aligned ion beams. The spacecraft is located well upstream of the foreshock edge and the bow shock, during a steady southward interplanetary magnetic field and in the absence of any solar wind or interplanetary magnetic field perturbations. This indicates the formation of such localized ion foreshocks.


2020 ◽  
Vol 125 (7) ◽  
Author(s):  
J. W. B. Eggington ◽  
J. P. Eastwood ◽  
L. Mejnertsen ◽  
R. T. Desai ◽  
J. P. Chittenden

2015 ◽  
Vol 120 (8) ◽  
pp. 6386-6408 ◽  
Author(s):  
Shan Wang ◽  
Lynn M. Kistler ◽  
Christopher G. Mouikis ◽  
Steven M. Petrinec

2020 ◽  
Author(s):  
Walter Gonzalez ◽  
Daiki Koga

<p>Magnetic reconnection permits topological rearrangements of the interplanetary and magnetospheric magnetic fields and the entry of solar wind mass, energy, and momentum into the magnetosphere. Thus, magnetic reconnection is a key issue to understand space weather. However, it hasnot been fully understood yet under which interplanetary/magnetosheath conditions magnetic reconnection takes place more effectively at the dayside magnetopause. For this purpose,  in the present study 25 dayside magnetopause reconnection events are investigated using the Time History of Events and Macroscale Interactions during Substorms ( THEMIS ) spacecraft  observations. It was found, (1) that the reconnection electric field is proportional to the interplanetary electric field, (2) that the reconnection electric field is inversely proportional to the solar wind-Alfvén Mach number,  (3) that thereconnection outflow speed is proportional to the solar wind Alfvén speed, and (4) that the reconnection outflow speed is  inversely proportional to the magnetosheath plasma beta. Finally, it is shown that the range of magnetic shear angles for which magnetic reconnection should occur is restricted to large shears as the magnetosheath flow direction becomes more perpendicular to the direction of the local magnetopause normal vector. Since these results refer to fairly typical solar wind-Alfvén Mach number condition, they may not apply to more extreme cases.</p>


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