Statistical study of auroral omega bands
The presence of very few statistical studies on auroral omega bands motivated us to test-use a semi-automatic method for identifying large-scale undulations of the diffuse aurora boundary and to investigate their occurrence. Five identical all-sky cameras with overlapping fields of view provided dat...
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Copernicus Publications
2017
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ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00009060 2023-05-15T16:13:00+02:00 Statistical study of auroral omega bands Partamies, Noora Weygand, James M. Juusola, Liisa 2017-09 electronic https://doi.org/10.5194/angeo-35-1069-2017 https://noa.gwlb.de/receive/cop_mods_00009060 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00009017/angeo-35-1069-2017.pdf https://angeo.copernicus.org/articles/35/1069/2017/angeo-35-1069-2017.pdf eng eng Copernicus Publications Annales Geophysicae -- http://www.bibliothek.uni-regensburg.de/ezeit/?1458425 -- https://www.ann-geophys.net/ -- https://www.ann-geophys.net/volumes.html -- http://link.springer.com/journal/585 -- 1432-0576 https://doi.org/10.5194/angeo-35-1069-2017 https://noa.gwlb.de/receive/cop_mods_00009060 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00009017/angeo-35-1069-2017.pdf https://angeo.copernicus.org/articles/35/1069/2017/angeo-35-1069-2017.pdf uneingeschränkt info:eu-repo/semantics/openAccess article Verlagsveröffentlichung article Text doc-type:article 2017 ftnonlinearchiv https://doi.org/10.5194/angeo-35-1069-2017 2022-02-08T22:57:45Z The presence of very few statistical studies on auroral omega bands motivated us to test-use a semi-automatic method for identifying large-scale undulations of the diffuse aurora boundary and to investigate their occurrence. Five identical all-sky cameras with overlapping fields of view provided data for 438 auroral omega-like structures over Fennoscandian Lapland from 1996 to 2007. The results from this set of omega band events agree remarkably well with previous observations of omega band occurrence in magnetic local time (MLT), lifetime, location between the region 1 and 2 field-aligned currents, as well as current density estimates. The average peak emission height of omega forms corresponds to the estimated precipitation energies of a few keV, which experienced no significant change during the events. Analysis of both local and global magnetic indices demonstrates that omega bands are observed during substorm expansion and recovery phases that are more intense than average substorm expansion and recovery phases in the same region. The omega occurrence with respect to the substorm expansion and recovery phases is in a very good agreement with an earlier observed distribution of fast earthward flows in the plasma sheet during expansion and recovery phases. These findings support the theory that omegas are produced by fast earthward flows and auroral streamers, despite the rarity of good conjugate observations. Article in Journal/Newspaper Fennoscandian Lapland Niedersächsisches Online-Archiv NOA Annales Geophysicae 35 5 1069 1083 |
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article Verlagsveröffentlichung Partamies, Noora Weygand, James M. Juusola, Liisa Statistical study of auroral omega bands |
topic_facet |
article Verlagsveröffentlichung |
description |
The presence of very few statistical studies on auroral omega bands motivated us to test-use a semi-automatic method for identifying large-scale undulations of the diffuse aurora boundary and to investigate their occurrence. Five identical all-sky cameras with overlapping fields of view provided data for 438 auroral omega-like structures over Fennoscandian Lapland from 1996 to 2007. The results from this set of omega band events agree remarkably well with previous observations of omega band occurrence in magnetic local time (MLT), lifetime, location between the region 1 and 2 field-aligned currents, as well as current density estimates. The average peak emission height of omega forms corresponds to the estimated precipitation energies of a few keV, which experienced no significant change during the events. Analysis of both local and global magnetic indices demonstrates that omega bands are observed during substorm expansion and recovery phases that are more intense than average substorm expansion and recovery phases in the same region. The omega occurrence with respect to the substorm expansion and recovery phases is in a very good agreement with an earlier observed distribution of fast earthward flows in the plasma sheet during expansion and recovery phases. These findings support the theory that omegas are produced by fast earthward flows and auroral streamers, despite the rarity of good conjugate observations. |
format |
Article in Journal/Newspaper |
author |
Partamies, Noora Weygand, James M. Juusola, Liisa |
author_facet |
Partamies, Noora Weygand, James M. Juusola, Liisa |
author_sort |
Partamies, Noora |
title |
Statistical study of auroral omega bands |
title_short |
Statistical study of auroral omega bands |
title_full |
Statistical study of auroral omega bands |
title_fullStr |
Statistical study of auroral omega bands |
title_full_unstemmed |
Statistical study of auroral omega bands |
title_sort |
statistical study of auroral omega bands |
publisher |
Copernicus Publications |
publishDate |
2017 |
url |
https://doi.org/10.5194/angeo-35-1069-2017 https://noa.gwlb.de/receive/cop_mods_00009060 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00009017/angeo-35-1069-2017.pdf https://angeo.copernicus.org/articles/35/1069/2017/angeo-35-1069-2017.pdf |
genre |
Fennoscandian Lapland |
genre_facet |
Fennoscandian Lapland |
op_relation |
Annales Geophysicae -- http://www.bibliothek.uni-regensburg.de/ezeit/?1458425 -- https://www.ann-geophys.net/ -- https://www.ann-geophys.net/volumes.html -- http://link.springer.com/journal/585 -- 1432-0576 https://doi.org/10.5194/angeo-35-1069-2017 https://noa.gwlb.de/receive/cop_mods_00009060 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00009017/angeo-35-1069-2017.pdf https://angeo.copernicus.org/articles/35/1069/2017/angeo-35-1069-2017.pdf |
op_rights |
uneingeschränkt info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/angeo-35-1069-2017 |
container_title |
Annales Geophysicae |
container_volume |
35 |
container_issue |
5 |
container_start_page |
1069 |
op_container_end_page |
1083 |
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1765998613925724160 |