Cluster observations of the magnetospheric low-latitude boundary layer and cusp during extreme solar wind and interplanetary magnetic field conditions: I. 10 November 2004 ICME

Y. V. Bogdanova; C. J. Owen; G. Siscoe; A. N. Fazakerley; I. Dandouras; O. Marghitu; Z. Kaymaz; H. Rème; E. A. Lucek

doi:10.1007/s11207-007-0417-1

Cluster observations of the magnetospheric low-latitude boundary layer and cusp during extreme solar wind and interplanetary magnetic field conditions: I. 10 November 2004 ICME

Y. V. Bogdanova^*, C. J. Owen, G. Siscoe, A. N. Fazakerley, I. Dandouras, O. Marghitu, Z. Kaymaz, H. Rème, E. A. Lucek

^*Corresponding author for this work

Department of Meteorological Engineering

Research output: Contribution to journal › Article › peer-review

4 Citations (Scopus)

Abstract

We present a study of the magnetospheric cusp response to extreme external parameters during passage of the ICME over the Earth on 10 November 2004, based on Cluster observations of the plasma properties inside the low-latitude boundary layer (LLBL)/cusp regions. Two separate events are observed while Cluster is in the dawn sector, 07∈-∈08 h magnetic local time (MLT). First, a LLBL/cusp crossing occurs during a period of strong southward IMF. During this time, the LLBL/cusp is very small, 0.8∈-∈1° invariant latitude (ILAT) and moves equatorward, down to 67° ILAT. This can be explained by the occurrence of significant magnetopause erosion due to enhanced dayside sub-solar reconnection. The energy of the plasma inside this region is higher than normal, and the low-energy cut-off often observed in the ion data is also unusually high. This might be explained by the suggestion that the local magnetosheath Alfvén velocity and deHoffmann∈-∈Teller velocity are also both extremely high. However, the plasma convection and parallel velocity inside this region are not very high. The second event discussed in this paper is a LLBL/cusp crossing during strong equatorial IMF (mostly due to the dominant dawn∈-∈dusk component). Under these conditions, occurring at the same time as pulses of solar wind dynamic pressure, the observations are very complicated. However, we suggest that in the polar region of the southern hemisphere, Cluster cross two LLBLs/cusps, spatially separated by polar cap plasma. The first LLBL/cusp is formed by anti-parallel reconnection in the dusk sector of the southern hemisphere and the second is formed by anti-parallel reconnection in the dawn sector of the northern hemisphere. The second LLBL/cusp is located at extremely low latitude, less than 66.3° ILAT. During all LLBL/cusp crossings, strong ionospheric O⁺ ion outflow is detected in the form of a narrow beam with limited pitch-angle range.

Original language	English
Pages (from-to)	201-232
Number of pages	32
Journal	Solar Physics
Volume	244
Issue number	1-2
DOIs	https://doi.org/10.1007/s11207-007-0417-1
Publication status	Published - Aug 2007

Funding

Acknowledgements The authors are grateful to L.K. Harra for organising the Sun – Earth Connection workshop at MSSL, from which this contribution is an outcome. This work is supported in the United Kingdom by the UCL/MSSL Particle Physics and Astronomy Research Council Rolling Grant. Y.V.B. thanks A.D. Lahiff and H.J. McAndrews for help with evaluating this paper. We would like to thank the CDAWeb team for providing the level 2 ACE MAG and ACE solar wind experiment data. We thank the OVT team for providing Cluster orbit and Cluster footprint plots.

Funders	Funder number
UCL/MSSL
Science and Technology Facilities Council	PP/E001173/1

Access to Document

10.1007/s11207-007-0417-1

Cite this

Bogdanova, Y. V., Owen, C. J., Siscoe, G., Fazakerley, A. N., Dandouras, I., Marghitu, O., Kaymaz, Z., Rème, H., & Lucek, E. A. (2007). Cluster observations of the magnetospheric low-latitude boundary layer and cusp during extreme solar wind and interplanetary magnetic field conditions: I. 10 November 2004 ICME. Solar Physics, 244(1-2), 201-232. https://doi.org/10.1007/s11207-007-0417-1

@article{d248cb9ccb20438982ef006b08af8e6d,

title = "Cluster observations of the magnetospheric low-latitude boundary layer and cusp during extreme solar wind and interplanetary magnetic field conditions: I. 10 November 2004 ICME",

abstract = "We present a study of the magnetospheric cusp response to extreme external parameters during passage of the ICME over the Earth on 10 November 2004, based on Cluster observations of the plasma properties inside the low-latitude boundary layer (LLBL)/cusp regions. Two separate events are observed while Cluster is in the dawn sector, 07∈-∈08 h magnetic local time (MLT). First, a LLBL/cusp crossing occurs during a period of strong southward IMF. During this time, the LLBL/cusp is very small, 0.8∈-∈1° invariant latitude (ILAT) and moves equatorward, down to 67° ILAT. This can be explained by the occurrence of significant magnetopause erosion due to enhanced dayside sub-solar reconnection. The energy of the plasma inside this region is higher than normal, and the low-energy cut-off often observed in the ion data is also unusually high. This might be explained by the suggestion that the local magnetosheath Alfv{\'e}n velocity and deHoffmann∈-∈Teller velocity are also both extremely high. However, the plasma convection and parallel velocity inside this region are not very high. The second event discussed in this paper is a LLBL/cusp crossing during strong equatorial IMF (mostly due to the dominant dawn∈-∈dusk component). Under these conditions, occurring at the same time as pulses of solar wind dynamic pressure, the observations are very complicated. However, we suggest that in the polar region of the southern hemisphere, Cluster cross two LLBLs/cusps, spatially separated by polar cap plasma. The first LLBL/cusp is formed by anti-parallel reconnection in the dusk sector of the southern hemisphere and the second is formed by anti-parallel reconnection in the dawn sector of the northern hemisphere. The second LLBL/cusp is located at extremely low latitude, less than 66.3° ILAT. During all LLBL/cusp crossings, strong ionospheric O+ ion outflow is detected in the form of a narrow beam with limited pitch-angle range.",

author = "Bogdanova, {Y. V.} and Owen, {C. J.} and G. Siscoe and Fazakerley, {A. N.} and I. Dandouras and O. Marghitu and Z. Kaymaz and H. R{\`e}me and Lucek, {E. A.}",

year = "2007",

month = aug,

doi = "10.1007/s11207-007-0417-1",

language = "English",

volume = "244",

pages = "201--232",

journal = "Solar Physics",

issn = "0038-0938",

publisher = "Springer Netherlands",

number = "1-2",

}

Bogdanova, YV, Owen, CJ, Siscoe, G, Fazakerley, AN, Dandouras, I, Marghitu, O, Kaymaz, Z, Rème, H & Lucek, EA 2007, 'Cluster observations of the magnetospheric low-latitude boundary layer and cusp during extreme solar wind and interplanetary magnetic field conditions: I. 10 November 2004 ICME', Solar Physics, vol. 244, no. 1-2, pp. 201-232. https://doi.org/10.1007/s11207-007-0417-1

TY - JOUR

T1 - Cluster observations of the magnetospheric low-latitude boundary layer and cusp during extreme solar wind and interplanetary magnetic field conditions

T2 - I. 10 November 2004 ICME

AU - Bogdanova, Y. V.

AU - Owen, C. J.

AU - Siscoe, G.

AU - Fazakerley, A. N.

AU - Dandouras, I.

AU - Marghitu, O.

AU - Kaymaz, Z.

AU - Rème, H.

AU - Lucek, E. A.

PY - 2007/8

Y1 - 2007/8

N2 - We present a study of the magnetospheric cusp response to extreme external parameters during passage of the ICME over the Earth on 10 November 2004, based on Cluster observations of the plasma properties inside the low-latitude boundary layer (LLBL)/cusp regions. Two separate events are observed while Cluster is in the dawn sector, 07∈-∈08 h magnetic local time (MLT). First, a LLBL/cusp crossing occurs during a period of strong southward IMF. During this time, the LLBL/cusp is very small, 0.8∈-∈1° invariant latitude (ILAT) and moves equatorward, down to 67° ILAT. This can be explained by the occurrence of significant magnetopause erosion due to enhanced dayside sub-solar reconnection. The energy of the plasma inside this region is higher than normal, and the low-energy cut-off often observed in the ion data is also unusually high. This might be explained by the suggestion that the local magnetosheath Alfvén velocity and deHoffmann∈-∈Teller velocity are also both extremely high. However, the plasma convection and parallel velocity inside this region are not very high. The second event discussed in this paper is a LLBL/cusp crossing during strong equatorial IMF (mostly due to the dominant dawn∈-∈dusk component). Under these conditions, occurring at the same time as pulses of solar wind dynamic pressure, the observations are very complicated. However, we suggest that in the polar region of the southern hemisphere, Cluster cross two LLBLs/cusps, spatially separated by polar cap plasma. The first LLBL/cusp is formed by anti-parallel reconnection in the dusk sector of the southern hemisphere and the second is formed by anti-parallel reconnection in the dawn sector of the northern hemisphere. The second LLBL/cusp is located at extremely low latitude, less than 66.3° ILAT. During all LLBL/cusp crossings, strong ionospheric O+ ion outflow is detected in the form of a narrow beam with limited pitch-angle range.

AB - We present a study of the magnetospheric cusp response to extreme external parameters during passage of the ICME over the Earth on 10 November 2004, based on Cluster observations of the plasma properties inside the low-latitude boundary layer (LLBL)/cusp regions. Two separate events are observed while Cluster is in the dawn sector, 07∈-∈08 h magnetic local time (MLT). First, a LLBL/cusp crossing occurs during a period of strong southward IMF. During this time, the LLBL/cusp is very small, 0.8∈-∈1° invariant latitude (ILAT) and moves equatorward, down to 67° ILAT. This can be explained by the occurrence of significant magnetopause erosion due to enhanced dayside sub-solar reconnection. The energy of the plasma inside this region is higher than normal, and the low-energy cut-off often observed in the ion data is also unusually high. This might be explained by the suggestion that the local magnetosheath Alfvén velocity and deHoffmann∈-∈Teller velocity are also both extremely high. However, the plasma convection and parallel velocity inside this region are not very high. The second event discussed in this paper is a LLBL/cusp crossing during strong equatorial IMF (mostly due to the dominant dawn∈-∈dusk component). Under these conditions, occurring at the same time as pulses of solar wind dynamic pressure, the observations are very complicated. However, we suggest that in the polar region of the southern hemisphere, Cluster cross two LLBLs/cusps, spatially separated by polar cap plasma. The first LLBL/cusp is formed by anti-parallel reconnection in the dusk sector of the southern hemisphere and the second is formed by anti-parallel reconnection in the dawn sector of the northern hemisphere. The second LLBL/cusp is located at extremely low latitude, less than 66.3° ILAT. During all LLBL/cusp crossings, strong ionospheric O+ ion outflow is detected in the form of a narrow beam with limited pitch-angle range.

UR - http://www.scopus.com/inward/record.url?scp=35348892549&partnerID=8YFLogxK

U2 - 10.1007/s11207-007-0417-1

DO - 10.1007/s11207-007-0417-1

M3 - Article

AN - SCOPUS:35348892549

SN - 0038-0938

VL - 244

SP - 201

EP - 232

JO - Solar Physics

JF - Solar Physics

IS - 1-2

ER -

Cluster observations of the magnetospheric low-latitude boundary layer and cusp during extreme solar wind and interplanetary magnetic field conditions: I. 10 November 2004 ICME

Abstract

Funding

Access to Document

Other files and links

Fingerprint

Cite this