Aspect sensitive E- and F-region SPEAR-enhanced incoherent backscatter observed by the EISCAT Svalbard radar
Previous studies of the aspect sensitivity of heater-enhanced incoherent radar backscatter in the high-latitude ionosphere have demonstrated the directional dependence of incoherent scatter signatures corresponding to artificially excited electrostatic waves, together with consistent field-aligned s...
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ftcopernicus:oai:publications.copernicus.org:angeo36637 2023-05-15T16:04:34+02:00 Aspect sensitive E- and F-region SPEAR-enhanced incoherent backscatter observed by the EISCAT Svalbard radar Dhillon, R. S. Robinson, T. R. Yeoman, T. K. 2018-09-27 application/pdf https://doi.org/10.5194/angeo-27-65-2009 https://angeo.copernicus.org/articles/27/65/2009/ eng eng doi:10.5194/angeo-27-65-2009 https://angeo.copernicus.org/articles/27/65/2009/ eISSN: 1432-0576 Text 2018 ftcopernicus https://doi.org/10.5194/angeo-27-65-2009 2020-07-20T16:26:45Z Previous studies of the aspect sensitivity of heater-enhanced incoherent radar backscatter in the high-latitude ionosphere have demonstrated the directional dependence of incoherent scatter signatures corresponding to artificially excited electrostatic waves, together with consistent field-aligned signatures that may be related to the presence of artificial field-aligned irregularities. These earlier high-latitude results have provided motivation for repeating the investigation in the different geophysical conditions that obtain in the polar cap ionosphere. The Space Plasma Exploration by Active Radar (SPEAR) facility is located within the polar cap and has provided observations of RF-enhanced ion and plasma line spectra recorded by the EISCAT Svalbard UHF incoherent scatter radar system (ESR), which is collocated with SPEAR. In this paper, we present observations of aspect sensitive E- and F-region SPEAR-induced ion and plasma line enhancements that indicate excitation of both the purely growing mode and the parametric decay instability, together with sporadic E-layer results that may indicate the presence of cavitons. We note consistent enhancements from field-aligned, vertical and also from 5° south of field-aligned. We attribute the prevalence of vertical scatter to the importance of the Spitze region, and of that from field-aligned to possible wave/irregularity coupling. Text EISCAT Svalbard Copernicus Publications: E-Journals Svalbard Annales Geophysicae 27 1 65 81 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
Previous studies of the aspect sensitivity of heater-enhanced incoherent radar backscatter in the high-latitude ionosphere have demonstrated the directional dependence of incoherent scatter signatures corresponding to artificially excited electrostatic waves, together with consistent field-aligned signatures that may be related to the presence of artificial field-aligned irregularities. These earlier high-latitude results have provided motivation for repeating the investigation in the different geophysical conditions that obtain in the polar cap ionosphere. The Space Plasma Exploration by Active Radar (SPEAR) facility is located within the polar cap and has provided observations of RF-enhanced ion and plasma line spectra recorded by the EISCAT Svalbard UHF incoherent scatter radar system (ESR), which is collocated with SPEAR. In this paper, we present observations of aspect sensitive E- and F-region SPEAR-induced ion and plasma line enhancements that indicate excitation of both the purely growing mode and the parametric decay instability, together with sporadic E-layer results that may indicate the presence of cavitons. We note consistent enhancements from field-aligned, vertical and also from 5° south of field-aligned. We attribute the prevalence of vertical scatter to the importance of the Spitze region, and of that from field-aligned to possible wave/irregularity coupling. |
format |
Text |
author |
Dhillon, R. S. Robinson, T. R. Yeoman, T. K. |
spellingShingle |
Dhillon, R. S. Robinson, T. R. Yeoman, T. K. Aspect sensitive E- and F-region SPEAR-enhanced incoherent backscatter observed by the EISCAT Svalbard radar |
author_facet |
Dhillon, R. S. Robinson, T. R. Yeoman, T. K. |
author_sort |
Dhillon, R. S. |
title |
Aspect sensitive E- and F-region SPEAR-enhanced incoherent backscatter observed by the EISCAT Svalbard radar |
title_short |
Aspect sensitive E- and F-region SPEAR-enhanced incoherent backscatter observed by the EISCAT Svalbard radar |
title_full |
Aspect sensitive E- and F-region SPEAR-enhanced incoherent backscatter observed by the EISCAT Svalbard radar |
title_fullStr |
Aspect sensitive E- and F-region SPEAR-enhanced incoherent backscatter observed by the EISCAT Svalbard radar |
title_full_unstemmed |
Aspect sensitive E- and F-region SPEAR-enhanced incoherent backscatter observed by the EISCAT Svalbard radar |
title_sort |
aspect sensitive e- and f-region spear-enhanced incoherent backscatter observed by the eiscat svalbard radar |
publishDate |
2018 |
url |
https://doi.org/10.5194/angeo-27-65-2009 https://angeo.copernicus.org/articles/27/65/2009/ |
geographic |
Svalbard |
geographic_facet |
Svalbard |
genre |
EISCAT Svalbard |
genre_facet |
EISCAT Svalbard |
op_source |
eISSN: 1432-0576 |
op_relation |
doi:10.5194/angeo-27-65-2009 https://angeo.copernicus.org/articles/27/65/2009/ |
op_doi |
https://doi.org/10.5194/angeo-27-65-2009 |
container_title |
Annales Geophysicae |
container_volume |
27 |
container_issue |
1 |
container_start_page |
65 |
op_container_end_page |
81 |
_version_ |
1766400153043861504 |