Ducted whistler-mode signals received at two widely spaced locations
Whistler-mode signals from a single VLF transmitter that have propagated in the same duct, have been observed simultaneously at Faraday, Antarctica (65°S, 64°W) and Dunedin, New Zealand (46°S, 171°E). The signals received have group-delay times that differ in the order of 10 ms, which can be explain...
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ftdoajarticles:oai:doaj.org/article:2e94846d975643cca87bf4f18e176590 2023-05-15T13:34:30+02:00 Ducted whistler-mode signals received at two widely spaced locations M. A. Clilverd N. R. Thomson A. J. Smith https://doaj.org/article/2e94846d975643cca87bf4f18e176590 EN eng Copernicus Publications http://www.ann-geophys.net/14/619/1996/angeo-14-619-1996.html https://doaj.org/toc/0992-7689 https://doaj.org/toc/1432-0576 0992-7689 1432-0576 https://doaj.org/article/2e94846d975643cca87bf4f18e176590 Annales Geophysicae, Vol 14, Iss 6, Pp 619-627 (0000) Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 article ftdoajarticles 2022-12-31T04:58:00Z Whistler-mode signals from a single VLF transmitter that have propagated in the same duct, have been observed simultaneously at Faraday, Antarctica (65°S, 64°W) and Dunedin, New Zealand (46°S, 171°E). The signals received have group-delay times that differ in the order of 10 ms, which can be explained by the differences in southern-hemisphere sub-ionospheric propagation time from duct exit region to receiver for the two sites. This difference has been used to determine the location of the duct exit region, with confirmation provided by arrival-bearing information from both sites. The whistler-mode signals typically occur one or two days after geomagnetic activity, with K p geq5. The sub-ionospheric-propagation model, LWPC, is used to estimate the whistler-mode power radiated from the duct exit region. These results are then combined with estimated loss values for ionospheric and ducted transmission to investigate the role of wave-particle amplification or absorption. On at least half of the events studied, plasmaspheric amplification of the signals appears to be needed to explain the observed whistler-mode signal strengths. Article in Journal/Newspaper Antarc* Antarctica Directory of Open Access Journals: DOAJ Articles New Zealand Faraday ENVELOPE(-64.256,-64.256,-65.246,-65.246) |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 |
spellingShingle |
Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 M. A. Clilverd N. R. Thomson A. J. Smith Ducted whistler-mode signals received at two widely spaced locations |
topic_facet |
Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 |
description |
Whistler-mode signals from a single VLF transmitter that have propagated in the same duct, have been observed simultaneously at Faraday, Antarctica (65°S, 64°W) and Dunedin, New Zealand (46°S, 171°E). The signals received have group-delay times that differ in the order of 10 ms, which can be explained by the differences in southern-hemisphere sub-ionospheric propagation time from duct exit region to receiver for the two sites. This difference has been used to determine the location of the duct exit region, with confirmation provided by arrival-bearing information from both sites. The whistler-mode signals typically occur one or two days after geomagnetic activity, with K p geq5. The sub-ionospheric-propagation model, LWPC, is used to estimate the whistler-mode power radiated from the duct exit region. These results are then combined with estimated loss values for ionospheric and ducted transmission to investigate the role of wave-particle amplification or absorption. On at least half of the events studied, plasmaspheric amplification of the signals appears to be needed to explain the observed whistler-mode signal strengths. |
format |
Article in Journal/Newspaper |
author |
M. A. Clilverd N. R. Thomson A. J. Smith |
author_facet |
M. A. Clilverd N. R. Thomson A. J. Smith |
author_sort |
M. A. Clilverd |
title |
Ducted whistler-mode signals received at two widely spaced locations |
title_short |
Ducted whistler-mode signals received at two widely spaced locations |
title_full |
Ducted whistler-mode signals received at two widely spaced locations |
title_fullStr |
Ducted whistler-mode signals received at two widely spaced locations |
title_full_unstemmed |
Ducted whistler-mode signals received at two widely spaced locations |
title_sort |
ducted whistler-mode signals received at two widely spaced locations |
publisher |
Copernicus Publications |
url |
https://doaj.org/article/2e94846d975643cca87bf4f18e176590 |
long_lat |
ENVELOPE(-64.256,-64.256,-65.246,-65.246) |
geographic |
New Zealand Faraday |
geographic_facet |
New Zealand Faraday |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_source |
Annales Geophysicae, Vol 14, Iss 6, Pp 619-627 (0000) |
op_relation |
http://www.ann-geophys.net/14/619/1996/angeo-14-619-1996.html https://doaj.org/toc/0992-7689 https://doaj.org/toc/1432-0576 0992-7689 1432-0576 https://doaj.org/article/2e94846d975643cca87bf4f18e176590 |
_version_ |
1766053773509132288 |