Optical observations geomagnetically conjugate to sprite-producing lightning discharges
International audience Theoretical studies have predicted that large positive cloud-to-ground discharges can trigger a runaway avalanche process of relativistic electrons, forming a geomagnetically trapped electron beam. The beam may undergo pitch angle and energy scattering during its traverse of t...
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ftinsu:oai:HAL:hal-00317857v1 2023-11-12T04:04:27+01:00 Optical observations geomagnetically conjugate to sprite-producing lightning discharges Marshall, R. A. Inan, U. S. Neubert, T. Hughes, A. Sátori, G. Bór, J. Collier, A. Allin, T. H. STARLab Stanford University Danish Space Research Institute (DSRI) University of KwaZulu-Natal Durban, Afrique du Sud (UKZN) Geodetic and Geophysical Research Institute (GGRI) Research Centre for Astronomy and Earth Sciences Budapest Hungarian Academy of Sciences (MTA)-Hungarian Academy of Sciences (MTA) Danmarks Tekniske Universitet = Technical University of Denmark (DTU) 2005-09-15 https://hal.science/hal-00317857 https://hal.science/hal-00317857/document https://hal.science/hal-00317857/file/angeo-23-2231-2005.pdf en eng HAL CCSD European Geosciences Union hal-00317857 https://hal.science/hal-00317857 https://hal.science/hal-00317857/document https://hal.science/hal-00317857/file/angeo-23-2231-2005.pdf info:eu-repo/semantics/OpenAccess ISSN: 0992-7689 EISSN: 1432-0576 Annales Geophysicae https://hal.science/hal-00317857 Annales Geophysicae, 2005, 23 (6), pp.2231-2237 [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/article Journal articles 2005 ftinsu 2023-10-25T16:25:08Z International audience Theoretical studies have predicted that large positive cloud-to-ground discharges can trigger a runaway avalanche process of relativistic electrons, forming a geomagnetically trapped electron beam. The beam may undergo pitch angle and energy scattering during its traverse of the Earth's magnetosphere, with a small percentage of electrons remaining in the loss cone and precipitating in the magnetically conjugate atmosphere. In particular, N 2 1P and N 2 + 1N optical emissions are expected to be observable. In July and August 2003, an attempt was made to detect these optical emissions, called "conjugate sprites", in correlation with sprite observations in Europe near . Sprite observations were made from the Observatoire du Pic du Midi (OMP) in the French Pyrenées, and VLF receivers were installed in Europe to detect causative sferics and ionospheric disturbances associated with sprites. In the Southern Hemisphere conjugate region, the Wide-angle Array for Sprite Photometry (WASP) was deployed at the South African Astronomical Observatory (SAAO), near Sutherland, South Africa, to observe optical emissions with a field-of-view magnetically conjugate to the Northern Hemisphere observing region. Observations at OMP revealed over 130 documented sprites, with WASP observations covering the conjugate region successfully for 30 of these events. However, no incidences of optical emissions in the conjugate hemisphere were found. Analysis of the conjugate optical data from SAAO, along with ELF energy measurements from Palmer Station, Antarctica, and charge-moment analysis, show that the lightning events during the course of this experiment likely had insufficient intensity to create a relativistic beam. Keywords. Ionosphere (Ionsophere-magnetosphere interactions; Ionospheric disturbances; Instruments and techniques) Article in Journal/Newspaper Antarc* Antarctica Institut national des sciences de l'Univers: HAL-INSU Palmer Station ENVELOPE(-64.050,-64.050,-64.770,-64.770) Palmer-Station ENVELOPE(-64.050,-64.050,-64.770,-64.770) Sutherland ENVELOPE(168.467,168.467,-77.500,-77.500) |
institution |
Open Polar |
collection |
Institut national des sciences de l'Univers: HAL-INSU |
op_collection_id |
ftinsu |
language |
English |
topic |
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU]Sciences of the Universe [physics]/Earth Sciences Marshall, R. A. Inan, U. S. Neubert, T. Hughes, A. Sátori, G. Bór, J. Collier, A. Allin, T. H. Optical observations geomagnetically conjugate to sprite-producing lightning discharges |
topic_facet |
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
International audience Theoretical studies have predicted that large positive cloud-to-ground discharges can trigger a runaway avalanche process of relativistic electrons, forming a geomagnetically trapped electron beam. The beam may undergo pitch angle and energy scattering during its traverse of the Earth's magnetosphere, with a small percentage of electrons remaining in the loss cone and precipitating in the magnetically conjugate atmosphere. In particular, N 2 1P and N 2 + 1N optical emissions are expected to be observable. In July and August 2003, an attempt was made to detect these optical emissions, called "conjugate sprites", in correlation with sprite observations in Europe near . Sprite observations were made from the Observatoire du Pic du Midi (OMP) in the French Pyrenées, and VLF receivers were installed in Europe to detect causative sferics and ionospheric disturbances associated with sprites. In the Southern Hemisphere conjugate region, the Wide-angle Array for Sprite Photometry (WASP) was deployed at the South African Astronomical Observatory (SAAO), near Sutherland, South Africa, to observe optical emissions with a field-of-view magnetically conjugate to the Northern Hemisphere observing region. Observations at OMP revealed over 130 documented sprites, with WASP observations covering the conjugate region successfully for 30 of these events. However, no incidences of optical emissions in the conjugate hemisphere were found. Analysis of the conjugate optical data from SAAO, along with ELF energy measurements from Palmer Station, Antarctica, and charge-moment analysis, show that the lightning events during the course of this experiment likely had insufficient intensity to create a relativistic beam. Keywords. Ionosphere (Ionsophere-magnetosphere interactions; Ionospheric disturbances; Instruments and techniques) |
author2 |
STARLab Stanford University Danish Space Research Institute (DSRI) University of KwaZulu-Natal Durban, Afrique du Sud (UKZN) Geodetic and Geophysical Research Institute (GGRI) Research Centre for Astronomy and Earth Sciences Budapest Hungarian Academy of Sciences (MTA)-Hungarian Academy of Sciences (MTA) Danmarks Tekniske Universitet = Technical University of Denmark (DTU) |
format |
Article in Journal/Newspaper |
author |
Marshall, R. A. Inan, U. S. Neubert, T. Hughes, A. Sátori, G. Bór, J. Collier, A. Allin, T. H. |
author_facet |
Marshall, R. A. Inan, U. S. Neubert, T. Hughes, A. Sátori, G. Bór, J. Collier, A. Allin, T. H. |
author_sort |
Marshall, R. A. |
title |
Optical observations geomagnetically conjugate to sprite-producing lightning discharges |
title_short |
Optical observations geomagnetically conjugate to sprite-producing lightning discharges |
title_full |
Optical observations geomagnetically conjugate to sprite-producing lightning discharges |
title_fullStr |
Optical observations geomagnetically conjugate to sprite-producing lightning discharges |
title_full_unstemmed |
Optical observations geomagnetically conjugate to sprite-producing lightning discharges |
title_sort |
optical observations geomagnetically conjugate to sprite-producing lightning discharges |
publisher |
HAL CCSD |
publishDate |
2005 |
url |
https://hal.science/hal-00317857 https://hal.science/hal-00317857/document https://hal.science/hal-00317857/file/angeo-23-2231-2005.pdf |
long_lat |
ENVELOPE(-64.050,-64.050,-64.770,-64.770) ENVELOPE(-64.050,-64.050,-64.770,-64.770) ENVELOPE(168.467,168.467,-77.500,-77.500) |
geographic |
Palmer Station Palmer-Station Sutherland |
geographic_facet |
Palmer Station Palmer-Station Sutherland |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_source |
ISSN: 0992-7689 EISSN: 1432-0576 Annales Geophysicae https://hal.science/hal-00317857 Annales Geophysicae, 2005, 23 (6), pp.2231-2237 |
op_relation |
hal-00317857 https://hal.science/hal-00317857 https://hal.science/hal-00317857/document https://hal.science/hal-00317857/file/angeo-23-2231-2005.pdf |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1782341619085737984 |