Multi-instrument study of the dynamic cusp during dominant IMF B-y conditions
We present multi-instrument observations using the meridian scanning photometer (MSP) at Ny Alesund, the ˚ EISCAT Svalbard radar (ESR) and the CUTLASS Finland HF radar, to investigate the dynamics of the cusp region during pulsed reconnection events. The optical data obtained from the MSP indicate t...
Main Authors: | , , , , |
---|---|
Format: | Other Non-Article Part of Journal/Newspaper |
Language: | unknown |
Published: |
2003
|
Subjects: | |
Online Access: | https://figshare.com/articles/journal_contribution/Multi-instrument_study_of_the_dynamic_cusp_during_dominant_IMF_B-y_conditions/10143584 |
id |
ftleicesterunfig:oai:figshare.com:article/10143584 |
---|---|
record_format |
openpolar |
spelling |
ftleicesterunfig:oai:figshare.com:article/10143584 2023-05-15T16:04:41+02:00 Multi-instrument study of the dynamic cusp during dominant IMF B-y conditions H. Khan M. Lester J. A. Davies S. E. Milan P. E. Sandholt 2003-03-31T00:00:00Z https://figshare.com/articles/journal_contribution/Multi-instrument_study_of_the_dynamic_cusp_during_dominant_IMF_B-y_conditions/10143584 unknown 2381/39329 https://figshare.com/articles/journal_contribution/Multi-instrument_study_of_the_dynamic_cusp_during_dominant_IMF_B-y_conditions/10143584 All Rights Reserved Uncategorized Science & Technology Physical Sciences Astronomy & Astrophysics Geosciences Multidisciplinary Meteorology & Atmospheric Sciences Geology ionosphere ionosphere-magnetosphere interactions particle precipitation magnetospheric physics FLUX-TRANSFER EVENTS INTERPLANETARY MAGNETIC-FIELD DAYSIDE AURORAL ACTIVITY HF RADAR OBSERVATIONS HIGH-LATITUDE CONVECTION CUTLASS FINLAND RADAR EISCAT SVALBARD RADAR IONOSPHERIC CONVECTION VELOCITY-MEASUREMENTS PLASMA CONVECTION Text Journal contribution 2003 ftleicesterunfig 2021-11-11T19:36:38Z We present multi-instrument observations using the meridian scanning photometer (MSP) at Ny Alesund, the ˚ EISCAT Svalbard radar (ESR) and the CUTLASS Finland HF radar, to investigate the dynamics of the cusp region during pulsed reconnection events. The optical data obtained from the MSP indicate the presence of several polewardmoving auroral forms (PMAFs) which have been previously identified as the auroral signature of pulsed reconnection. Furthermore, the optical green line (557.7 nm) luminosity indicates a loss of emission equatorward of the location of the onset of the PMAFs, characteristic of magnetospheric plasma escaping to the magnetosheath along newly opened field lines. This reduction in green line luminosity creates a “dark region”, the equatorward edge of which is found to lie close to the boundary between high and low spectral widths observed by the CUTLASS Finland radar. High spectral widths on the dayside have previously been identified as a good indicator of cusp backscatter. Both of these boundaries have been suggested to provide an accurate representation of the location of the open/closed field line boundary. The ESR observations show enhancements in electron density and electron temperature occurring in conjunction with the optical PMAFs. The observations demonstrate some correspondence with the theoretical predictions of Davis and Lockwood (1996), who used an auroral precipitation model to predict ESR observations in the vicinity of the cusp. However, the limitations of this model are apparent under conditions of large plasma flows in the ionosphere. Finally, convection velocities obtained from the HF radar data illustrate a flow regime similar to that predicted to be driven by strong IMF By , as described by Cowley and Lockwood (1992), demonstrating an initial azimuthal flow followed by a rotation to more poleward directions. Other Non-Article Part of Journal/Newspaper EISCAT Svalbard University of Leicester: Figshare Svalbard Lockwood ENVELOPE(167.400,167.400,-84.150,-84.150) Cowley ENVELOPE(-134.909,-134.909,60.518,60.518) |
institution |
Open Polar |
collection |
University of Leicester: Figshare |
op_collection_id |
ftleicesterunfig |
language |
unknown |
topic |
Uncategorized Science & Technology Physical Sciences Astronomy & Astrophysics Geosciences Multidisciplinary Meteorology & Atmospheric Sciences Geology ionosphere ionosphere-magnetosphere interactions particle precipitation magnetospheric physics FLUX-TRANSFER EVENTS INTERPLANETARY MAGNETIC-FIELD DAYSIDE AURORAL ACTIVITY HF RADAR OBSERVATIONS HIGH-LATITUDE CONVECTION CUTLASS FINLAND RADAR EISCAT SVALBARD RADAR IONOSPHERIC CONVECTION VELOCITY-MEASUREMENTS PLASMA CONVECTION |
spellingShingle |
Uncategorized Science & Technology Physical Sciences Astronomy & Astrophysics Geosciences Multidisciplinary Meteorology & Atmospheric Sciences Geology ionosphere ionosphere-magnetosphere interactions particle precipitation magnetospheric physics FLUX-TRANSFER EVENTS INTERPLANETARY MAGNETIC-FIELD DAYSIDE AURORAL ACTIVITY HF RADAR OBSERVATIONS HIGH-LATITUDE CONVECTION CUTLASS FINLAND RADAR EISCAT SVALBARD RADAR IONOSPHERIC CONVECTION VELOCITY-MEASUREMENTS PLASMA CONVECTION H. Khan M. Lester J. A. Davies S. E. Milan P. E. Sandholt Multi-instrument study of the dynamic cusp during dominant IMF B-y conditions |
topic_facet |
Uncategorized Science & Technology Physical Sciences Astronomy & Astrophysics Geosciences Multidisciplinary Meteorology & Atmospheric Sciences Geology ionosphere ionosphere-magnetosphere interactions particle precipitation magnetospheric physics FLUX-TRANSFER EVENTS INTERPLANETARY MAGNETIC-FIELD DAYSIDE AURORAL ACTIVITY HF RADAR OBSERVATIONS HIGH-LATITUDE CONVECTION CUTLASS FINLAND RADAR EISCAT SVALBARD RADAR IONOSPHERIC CONVECTION VELOCITY-MEASUREMENTS PLASMA CONVECTION |
description |
We present multi-instrument observations using the meridian scanning photometer (MSP) at Ny Alesund, the ˚ EISCAT Svalbard radar (ESR) and the CUTLASS Finland HF radar, to investigate the dynamics of the cusp region during pulsed reconnection events. The optical data obtained from the MSP indicate the presence of several polewardmoving auroral forms (PMAFs) which have been previously identified as the auroral signature of pulsed reconnection. Furthermore, the optical green line (557.7 nm) luminosity indicates a loss of emission equatorward of the location of the onset of the PMAFs, characteristic of magnetospheric plasma escaping to the magnetosheath along newly opened field lines. This reduction in green line luminosity creates a “dark region”, the equatorward edge of which is found to lie close to the boundary between high and low spectral widths observed by the CUTLASS Finland radar. High spectral widths on the dayside have previously been identified as a good indicator of cusp backscatter. Both of these boundaries have been suggested to provide an accurate representation of the location of the open/closed field line boundary. The ESR observations show enhancements in electron density and electron temperature occurring in conjunction with the optical PMAFs. The observations demonstrate some correspondence with the theoretical predictions of Davis and Lockwood (1996), who used an auroral precipitation model to predict ESR observations in the vicinity of the cusp. However, the limitations of this model are apparent under conditions of large plasma flows in the ionosphere. Finally, convection velocities obtained from the HF radar data illustrate a flow regime similar to that predicted to be driven by strong IMF By , as described by Cowley and Lockwood (1992), demonstrating an initial azimuthal flow followed by a rotation to more poleward directions. |
format |
Other Non-Article Part of Journal/Newspaper |
author |
H. Khan M. Lester J. A. Davies S. E. Milan P. E. Sandholt |
author_facet |
H. Khan M. Lester J. A. Davies S. E. Milan P. E. Sandholt |
author_sort |
H. Khan |
title |
Multi-instrument study of the dynamic cusp during dominant IMF B-y conditions |
title_short |
Multi-instrument study of the dynamic cusp during dominant IMF B-y conditions |
title_full |
Multi-instrument study of the dynamic cusp during dominant IMF B-y conditions |
title_fullStr |
Multi-instrument study of the dynamic cusp during dominant IMF B-y conditions |
title_full_unstemmed |
Multi-instrument study of the dynamic cusp during dominant IMF B-y conditions |
title_sort |
multi-instrument study of the dynamic cusp during dominant imf b-y conditions |
publishDate |
2003 |
url |
https://figshare.com/articles/journal_contribution/Multi-instrument_study_of_the_dynamic_cusp_during_dominant_IMF_B-y_conditions/10143584 |
long_lat |
ENVELOPE(167.400,167.400,-84.150,-84.150) ENVELOPE(-134.909,-134.909,60.518,60.518) |
geographic |
Svalbard Lockwood Cowley |
geographic_facet |
Svalbard Lockwood Cowley |
genre |
EISCAT Svalbard |
genre_facet |
EISCAT Svalbard |
op_relation |
2381/39329 https://figshare.com/articles/journal_contribution/Multi-instrument_study_of_the_dynamic_cusp_during_dominant_IMF_B-y_conditions/10143584 |
op_rights |
All Rights Reserved |
_version_ |
1766400291067920384 |