Velocity shear-related ion upflow in the low-altitude ionosphere
Abstract. Strong ion upflows with field-aligned velocity above 1000 ms−1 were observed by the European Incoherent Scatter (EISCAT) UHF Radar at Tromsø, Norway in the dayside auroral region at heights between 500–600 km during the 15 May 1997 magnetic storm. Both the EISCAT observations and the Assim...
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ftciteseerx:oai:CiteSeerX.psu:10.1.1.210.2969 2023-05-15T16:04:30+02:00 Velocity shear-related ion upflow in the low-altitude ionosphere H. Liu G. Lu The Pennsylvania State University CiteSeerX Archives application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.210.2969 http://www.ann-geophys.net/22/1149/2004/angeo-22-1149-2004.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.210.2969 http://www.ann-geophys.net/22/1149/2004/angeo-22-1149-2004.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://www.ann-geophys.net/22/1149/2004/angeo-22-1149-2004.pdf text ftciteseerx 2016-01-07T17:49:21Z Abstract. Strong ion upflows with field-aligned velocity above 1000 ms−1 were observed by the European Incoherent Scatter (EISCAT) UHF Radar at Tromsø, Norway in the dayside auroral region at heights between 500–600 km during the 15 May 1997 magnetic storm. Both the EISCAT observations and the Assimilative Mapping of Ionospheric Electrodynamics (AMIE) simulation results show that this event occurred in a region with low Joule heating rate, but with strong velocity shear. During the same period, the electron density and temperature showed no sign of soft particle precipitation, which is consistent with the UVI images from the POLAR satellite, thus excluding possible ion energization through soft particle precipitation. Our simple calculation shows that the velocity shear can provide sufficient energy for the observed ion upflow, thus suggesting shear-driven instabilities as a possible heating mechanism. Key words. Ionosphere, particle acceleration, magnetospheric physics 1 Text EISCAT Tromsø Unknown Norway Tromsø |
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Open Polar |
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Unknown |
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ftciteseerx |
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English |
description |
Abstract. Strong ion upflows with field-aligned velocity above 1000 ms−1 were observed by the European Incoherent Scatter (EISCAT) UHF Radar at Tromsø, Norway in the dayside auroral region at heights between 500–600 km during the 15 May 1997 magnetic storm. Both the EISCAT observations and the Assimilative Mapping of Ionospheric Electrodynamics (AMIE) simulation results show that this event occurred in a region with low Joule heating rate, but with strong velocity shear. During the same period, the electron density and temperature showed no sign of soft particle precipitation, which is consistent with the UVI images from the POLAR satellite, thus excluding possible ion energization through soft particle precipitation. Our simple calculation shows that the velocity shear can provide sufficient energy for the observed ion upflow, thus suggesting shear-driven instabilities as a possible heating mechanism. Key words. Ionosphere, particle acceleration, magnetospheric physics 1 |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
H. Liu G. Lu |
spellingShingle |
H. Liu G. Lu Velocity shear-related ion upflow in the low-altitude ionosphere |
author_facet |
H. Liu G. Lu |
author_sort |
H. Liu |
title |
Velocity shear-related ion upflow in the low-altitude ionosphere |
title_short |
Velocity shear-related ion upflow in the low-altitude ionosphere |
title_full |
Velocity shear-related ion upflow in the low-altitude ionosphere |
title_fullStr |
Velocity shear-related ion upflow in the low-altitude ionosphere |
title_full_unstemmed |
Velocity shear-related ion upflow in the low-altitude ionosphere |
title_sort |
velocity shear-related ion upflow in the low-altitude ionosphere |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.210.2969 http://www.ann-geophys.net/22/1149/2004/angeo-22-1149-2004.pdf |
geographic |
Norway Tromsø |
geographic_facet |
Norway Tromsø |
genre |
EISCAT Tromsø |
genre_facet |
EISCAT Tromsø |
op_source |
http://www.ann-geophys.net/22/1149/2004/angeo-22-1149-2004.pdf |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.210.2969 http://www.ann-geophys.net/22/1149/2004/angeo-22-1149-2004.pdf |
op_rights |
Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
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1766400082364596224 |