Effects of the dipole tilt and northward and duskward IMF on dayside magnetic reconnection in a global MHD simulation

Park, K. S.; Ogino, T.; Kim, Y. H.

doi:10.1029/2009ja014212

Cited by 12 publications

(18 citation statements)

References 11 publications

(21 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…There are two reconnection sites: one in the northern dawn sector (A) and the other in the southern dusk sector (B), where the field lines are antiparallel between the northward and dawnward IMF and geomagnetic field lines. We find that the dayside reconnection signatures here show similar characteristics to those for north-duskward IMF conditions in Park et al [2010]. The high-latitude reconnection starts at t = 20 min, and then the tail reconnection begins from t = 40 min after the solar wind and IMF parameter enter the simulation box.…”

Section: 1002/2015ja021005supporting

confidence: 58%

“…Based on the same methods as for case 1 above, we determined the magnetic reconnection to occur at high latitudes at the dawn sector in the northern hemisphere (A) and at the dusk sector in the southern hemisphere (B), where the IMF field lines are antiparallel to the geomagnetic field lines [Park et al, 2010]. The thick solid (blue and yellow) lines connect to the southern ionosphere, and the thick dashed line connects to the northern ionosphere.…”

Section: 1002/2015ja021005mentioning

confidence: 99%

“…In this work, we follow the same methods as in Park et al [2006Park et al [ , 2010 to determine characteristics of dayside reconnection in the presence of the IMF B y and/or dipole tilt, which breaks all of the symmetry in the location of dayside reconnection. We define the region with highly kinked open field lines as the reconnection site on the dayside.…”

Section: Casementioning

confidence: 99%

“…Previous global MHD simulations of the interaction of northward IMF solar wind with the Earth's magnetosphere have successfully reproduced variations in the global configuration of the magnetosphere [Ogino and Walker, 1984;Ogino et al, 1985;Raeder et al, 1995Raeder et al, , 1997Berchem et al, 1995;Tanaka, 1999;Song et al, 2000;Li et al, 2009;Park et al, 2010]. For example, Li et al [2009] demonstrated the formation mechanism of the dayside cold dense plasma layer (CDPL) by using the global MHD simulation model OpenGGCM.…”

Section: Introductionmentioning

confidence: 99%

“…They found that most of the plasma in CDPL originates from the magnetosheath plasma by the double high-latitude reconnection process under the northward IMF. Park et al [2010] have studied dayside magnetic reconnection by using a three-dimensional global MHD simulation as a function of dipole tilt and northward and duskward IMF components. They found that the reconnection during northward IMF predominantly occurs at high latitudes where antiparallel field regions appear in the northern dusk sector and in the southern dawn sector.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

MHD simulations using average solar wind conditions for substorms observed under northward IMF conditions

et al. 2015

Self Cite

View full text Add to dashboard Cite

Substorms are known to sometimes occur even under northward interplanetary magnetic field (IMF) conditions. In this paper, we perform three‐dimensional global magnetohydrodynamic simulations to examine dayside reconnection, tail, and ionospheric signatures for two cases of substorm observations under prolonged northward and dawnward IMF conditions: (1) a strongly northward/dawnward IMF case with BIMF = (0, −20, 20) nT; (2) a weakly northward/dawnward IMF case with BIMF = (0, −2, 2) nT. Throughout the simulations, we used the constant solar wind conditions to reflect the prolonged solar wind conditions around the substorm times. We found that, in both cases, the tail reconnection occurred after the usual high‐latitude reconnection on the dayside, providing a possible energy source for later triggered substorm observations under northward IMF conditions. The presence of an equal amount of IMF By allows the high‐latitude reconnected magnetic field lines to transport to the tail lobe, eventually leading to the tail reconnection. The simulation results also revealed the following major differences between the two cases: First, the reconnection onset (both on dayside and in the tail) occurs earlier in the strongly northward IMF case than in the weakly northward IMF case. Second, the polar cap size, which is finite in both cases despite the northward IMF conditions and thus supports the lobe energy buildup needed for the substorm occurrences, is larger in the strongly northward IMF case. Accordingly, the polar cap potential is far larger in the strongly northward IMF case (hundreds of kilovolt) than in the weakly northward IMF case (tens of kilovolt). Third, in the strongly northward IMF case, the strong earthward tail plasma flow appears to be caused by the enhanced convection (so enhanced duskward Ey) due to the tail reconnection. In contrast, in the weakly northward IMF case, the earthward tail plasma flow increases gradually in association with a modestly increased duskward electric field. In addition, the inner plasma pressure and the cross tail current near the reconnection site increase significantly in the strongly northward IMF case but less significantly in the weakly northward IMF case after the onset of the tail reconnection. In conclusion, the simulation results support observations of the substorms under northward IMF conditions in the presence of an equal amount of IMF By by demonstrating the energy input via dayside reconnection and the subsequent occurrence of the tail reconnection.

show abstract

Section: 1002/2015ja021005supporting

confidence: 58%

Section: 1002/2015ja021005mentioning

confidence: 99%

Section: Casementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

MHD simulations using average solar wind conditions for substorms observed under northward IMF conditions

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

Relation between cusp ion structures and dayside reconnection for four IMF clock angles: OpenGGCM‐LTPT results

et al. 2015

View full text Add to dashboard Cite

When, where, and which type of reconnection (antiparallel or component) happens on the dayside magnetopause are long‐standing unsolved questions due to insufficient in situ observation of reconnection sites. Previous studies showed that the dispersed ion signatures observed in the magnetospheric cusps depend on the reconnection mechanism, suggesting that cusp ion signatures can be a good tool to investigate the locations and properties of dayside reconnection. We investigate this close relation between cusp signatures and magnetopause reconnection for four different interplanetary magnetic field (IMF) clock angles (CA) using the Open Global Geospace Circulation Model (OpenGGCM) and the Liouville Theorem Particle Tracer(LTPT). OpenGGCM produces dayside reconnection under the resistive MHD theory, and LTPT calculates cusp ion signatures caused by the simulated reconnection. Our model results show that for CA = 0∘, antiparallel reconnection at both the northern and southern lobes causes a reverse dispersion in which ion energies increase with increasing latitude. For CA = 60∘, unsteady antiparallel reconnection at both the northern and southern lobes causes double reverse dispersions. For CA = 120∘, component reconnection near the subsolar point produces a dispersionless signature in the low‐latitude cusp, and antiparallel reconnection on the duskside northern magnetopause produces a normal dispersion in the high‐latitude cusp in which ion energies decrease with increasing latitude. For CA = 180∘, antiparallel reconnection near the subsolar point causes a normal dispersion.

show abstract

The formation of superdense plasma sheet in association with the IMF turning from northward to southward

Raeder

Thomsen

et al. 2017

JGR Space Physics

View full text Add to dashboard Cite

We have studied two events in which relatively superdense plasma appeared near geosynchronous orbit after the interplanetary magnetic field (IMF) changed from a long period of northward condition to southward condition. We used the magnetosphere MHD model Open Geospace General Circulation Model to simulate these two events and compared the simulation results with observations. The observations and the simulation results show that an extended period of northward IMF caused a cold dense plasma sheet (CDPS) to form in the near tail, and a subsequent southward IMF caused a highly stretched near‐tail dipole field, which enhanced the earthward convection and eventually set off reconnection. Some of the cold dense plasma was thus consequently transported to geosynchronous orbit and formed a superdense plasma sheet (SDPS). CDPS is the main source of SDPS in its early stage after the IMF southward turning.

show abstract

Effects of the dipole tilt and northward and duskward IMF on dayside magnetic reconnection in a global MHD simulation

Cited by 12 publications

References 11 publications

MHD simulations using average solar wind conditions for substorms observed under northward IMF conditions

MHD simulations using average solar wind conditions for substorms observed under northward IMF conditions

Relation between cusp ion structures and dayside reconnection for four IMF clock angles: OpenGGCM‐LTPT results

The formation of superdense plasma sheet in association with the IMF turning from northward to southward

Contact Info

Product

Resources

About