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- Keyword
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- Current ring (2)
- Magnetic storm (2)
- Magnetosphere (2)
- Storms (2)
- Auroral field (1)
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- Auroral field liines (1)
- CAMMICE (1)
- Equatorial plasma sheet (1)
- Geomagnetic field (1)
- Inner magnetosphere (1)
- Ionosphere (1)
- Magnetospheric substorm (1)
- Magnetospheric substorm signature (1)
- POLAR (1)
- Plasma sheet (1)
- Plasma sheet particles (1)
- Polar spacecraft (1)
- Poynting flux (1)
- Signatures (1)
- Substorm onset (1)
- Timing (1)
Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
Reconciliation Of The Substorm Onset Determined On The Ground And At The Polar Spacecraft, P K. Toivanen, D N. Baker, W K. Peterson, H J. Singer, Niescja E. Turner, X Li, K Kauristie, M Syrjasuo, A Keiling, C A. Kletzing
Reconciliation Of The Substorm Onset Determined On The Ground And At The Polar Spacecraft, P K. Toivanen, D N. Baker, W K. Peterson, H J. Singer, Niescja E. Turner, X Li, K Kauristie, M Syrjasuo, A Keiling, C A. Kletzing
Physics and Astronomy Faculty Research
An isolated substorm on Oct. 17, 1997 during a close conjunction of the Polar spacecraft and the ground-based MIRACLE network is studied in detail. We identify signatures of substorm onset in the plasma sheet midway between the ionosphere and the equatorial plasma sheet, determine their timing relative to the ground signatures, and discuss their counterparts on the ground and in the equatorial plasma sheet. The substorm onset is determined as the negative bay onset at 2040:42(≠ 5 sec) UT coinciding with the onset of auroral precipitation, energization of plasma sheet electrons at Polar, and strong magnetic field variations perpendicular to …
Entry Of Plasma Sheet Particles Into The Inner Magnetosphere Observed By Polar/Cammice, N Yu Ganushkina, T I. Pulkkinen, V A. Sergeev, M V. Kubyshkina, D N. Baker, Niescja E. Turner, M Grande, B Kellett, J F. Fennell, J L. Roeder, J A. Sauvaud, T A. Fritz
Entry Of Plasma Sheet Particles Into The Inner Magnetosphere Observed By Polar/Cammice, N Yu Ganushkina, T I. Pulkkinen, V A. Sergeev, M V. Kubyshkina, D N. Baker, Niescja E. Turner, M Grande, B Kellett, J F. Fennell, J L. Roeder, J A. Sauvaud, T A. Fritz
Physics and Astronomy Faculty Research
Statistical results are presented from Polar/CAMMICE measurements of events during which the plasma sheet ions have penetrated deeply into the inner magnetosphere. Owing to their characteristic structure in energy-time spectrograms, these events are called "intense nose events." Almost 400 observations of such structures were made during 1997. Intense nose events are shown to be more frequent in the dusk than in the dawn sector. They typically penetrate well inside L = 4, the deepest penetration having occurred around midnight and noon. The intense nose events are associated with magnetic (substorm) activity. However, even moderate activity (AE = 150-250 nT) resulted …
Evaluation Of The Tail Current Contribution To Dst, Niescja E. Turner, D N. Baker, T I. Pulkkinen, R L. Mcpherron
Evaluation Of The Tail Current Contribution To Dst, Niescja E. Turner, D N. Baker, T I. Pulkkinen, R L. Mcpherron
Physics and Astronomy Faculty Research
The Dst index is produced using low-latitude ground magnetic field measurements and frequently is used as an estimate of the energy density of the ring current carried mainly by energetic (∼10-200 keV) ions relatively close to the Earth. However, other magnetospheric current systems can cause field perturbations at the Earth's surface: for example, dayside magnetopause currents are known to contribute to the Dst index. It has also been suggested that the nightside tail current sheet can significantly affect the Dst index during high magnetic activity periods when the currents are intense and flow relatively close to the Earth. In this …
A Substorm Onset Observed By The Polar Spacecraft In Conjunction With The Image Chain, P K. Toivanen, D N. Baker, W K. Peterson, A Viljanen, Niescja E. Turner, X Li, C A. Kletzing
A Substorm Onset Observed By The Polar Spacecraft In Conjunction With The Image Chain, P K. Toivanen, D N. Baker, W K. Peterson, A Viljanen, Niescja E. Turner, X Li, C A. Kletzing
Physics and Astronomy Faculty Research
We present observations of the Polar spacecraft of magnetospheric substorm signatures in the plasma sheet midway along auroral field lines between the ionosphere and the equatorial plasma sheet. An isolated substorm on October 17, 1997, is studied in detail. The onset time at 2040:42 UT was defined to be almost simultaneous (within 20 sec) on the ground and at Polar altitude (~ 4RE. At Polar, the onset was manifested as strong magnetic field variations and plasma flow bursts with amplitudes exceeding 20 nT and 100 km/s, respectively. Bursts of parallel Poynting flux of ~ 0.5 ergs/cm2 …