Modification of the high latitude ionosphere F region by X-mode powerful HF radio waves: Experimental results from multi-instrument diagnostics
The file associated with this record is under a 24-month embargo from publication in accordance with the publisher's self-archiving policy. The full text may be available through the publisher links provided above. We present experimental results concentrating on a variety of phenomena in the h...
Published in: | Journal of Atmospheric and Solar-Terrestrial Physics |
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Main Authors: | , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Elsevier
2016
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Subjects: | |
Online Access: | http://www.sciencedirect.com/science/article/pii/S1364682615300705 http://hdl.handle.net/2381/36451 https://doi.org/10.1016/j.jastp.2015.10.009 |
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ftleicester:oai:lra.le.ac.uk:2381/36451 |
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record_format |
openpolar |
institution |
Open Polar |
collection |
University of Leicester: Leicester Research Archive (LRA) |
op_collection_id |
ftleicester |
language |
English |
topic |
Science & Technology Physical Sciences Geochemistry & Geophysics Meteorology & Atmospheric Sciences Ionosphere (active experiments) Radio Science (nonlinear phenomena) STIMULATED BRILLOUIN-SCATTERING ION GYROHARMONIC STRUCTURES ASPECT ANGLE DEPENDENCE HEATING EXPERIMENTS LANGMUIR TURBULENCE MAGNETIC ZENITH ELECTROMAGNETIC EMISSIONS INCOHERENT BACKSCATTER ENHANCED PLASMA INDUCED AIRGLOW |
spellingShingle |
Science & Technology Physical Sciences Geochemistry & Geophysics Meteorology & Atmospheric Sciences Ionosphere (active experiments) Radio Science (nonlinear phenomena) STIMULATED BRILLOUIN-SCATTERING ION GYROHARMONIC STRUCTURES ASPECT ANGLE DEPENDENCE HEATING EXPERIMENTS LANGMUIR TURBULENCE MAGNETIC ZENITH ELECTROMAGNETIC EMISSIONS INCOHERENT BACKSCATTER ENHANCED PLASMA INDUCED AIRGLOW Blagoveshchenskaya, N. F. Borisova, T. D. Yeoman, Timothy Kenneth Haggstrom, I. Kalishin, A. S. Modification of the high latitude ionosphere F region by X-mode powerful HF radio waves: Experimental results from multi-instrument diagnostics |
topic_facet |
Science & Technology Physical Sciences Geochemistry & Geophysics Meteorology & Atmospheric Sciences Ionosphere (active experiments) Radio Science (nonlinear phenomena) STIMULATED BRILLOUIN-SCATTERING ION GYROHARMONIC STRUCTURES ASPECT ANGLE DEPENDENCE HEATING EXPERIMENTS LANGMUIR TURBULENCE MAGNETIC ZENITH ELECTROMAGNETIC EMISSIONS INCOHERENT BACKSCATTER ENHANCED PLASMA INDUCED AIRGLOW |
description |
The file associated with this record is under a 24-month embargo from publication in accordance with the publisher's self-archiving policy. The full text may be available through the publisher links provided above. We present experimental results concentrating on a variety of phenomena in the high latitude ionosphere F2 layer induced by an extraordinary (X-mode) HF pump wave at high heater frequencies (f[Subscript: H]=6.2–8.0 MHz), depending on the pump frequency proximity to the ordinary and extraordinary mode critical frequencies, foF2 and fxF2. The experiments were carried out at the EISCAT HF heating facility with an effective radiated power of 450–650 MW in October 2012 and October–November 2013. Their distinctive feature is a wide diapason of critical frequency changes, when the f[Subscript: H]/foF2 ratio was varied through a wide range from 0.9 to 1.35. It provides both a proper comparison of X-mode HF-induced phenomena excited under different ratios of f[Subscript: H]/foF2 and an estimation of the frequency range above foF2 in which such X-mode phenomena are still possible. It was shown that the HF-enhanced ion and plasma lines are excited above foF2 when the HF pump frequency is lying in range between the foF2 and fxF2, foF2≤f[Subscript: H]≤fxF2, whereas small-scale field-aligned irregularities continued to be generated even when f[Subscript: H] exceeded fxF2 by up to 1 MHz and an X-polarized pump wave cannot be reflected from the ionosphere. Another parameter of importance is the magnetic zenith effect (HF beam/radar angle direction) which is typical for X-mode phenomena under f[Subscript: H]/foF2 >1 as well as f[Subscript: H]/foF2 ≤1. We have shown for the first time that an X-mode HF pump wave is able to generate strong narrowband spectral components in the SEE spectra (within 1 kHz of pump frequency) in the ionosphere F region, which were recorded at distance of 1200 km from the HF heating facility. The observed spectral lines can be associated with the ion acoustic, electrostatic ion cyclotron, and electrostatic ion cyclotron harmonic waves (otherwise known as neutralized ion Bernstein waves). The comparison between the O- and X-mode SEE spectra recorded at distance far from HF heating facility clearly demonstrated that variety of the narrowband spectral structures were only observed under X-mode HF pumping. The potential generation mechanisms of the different narrowband spectral components are discussed. Peer-reviewed Post-print |
format |
Article in Journal/Newspaper |
author |
Blagoveshchenskaya, N. F. Borisova, T. D. Yeoman, Timothy Kenneth Haggstrom, I. Kalishin, A. S. |
author_facet |
Blagoveshchenskaya, N. F. Borisova, T. D. Yeoman, Timothy Kenneth Haggstrom, I. Kalishin, A. S. |
author_sort |
Blagoveshchenskaya, N. F. |
title |
Modification of the high latitude ionosphere F region by X-mode powerful HF radio waves: Experimental results from multi-instrument diagnostics |
title_short |
Modification of the high latitude ionosphere F region by X-mode powerful HF radio waves: Experimental results from multi-instrument diagnostics |
title_full |
Modification of the high latitude ionosphere F region by X-mode powerful HF radio waves: Experimental results from multi-instrument diagnostics |
title_fullStr |
Modification of the high latitude ionosphere F region by X-mode powerful HF radio waves: Experimental results from multi-instrument diagnostics |
title_full_unstemmed |
Modification of the high latitude ionosphere F region by X-mode powerful HF radio waves: Experimental results from multi-instrument diagnostics |
title_sort |
modification of the high latitude ionosphere f region by x-mode powerful hf radio waves: experimental results from multi-instrument diagnostics |
publisher |
Elsevier |
publishDate |
2016 |
url |
http://www.sciencedirect.com/science/article/pii/S1364682615300705 http://hdl.handle.net/2381/36451 https://doi.org/10.1016/j.jastp.2015.10.009 |
long_lat |
ENVELOPE(-67.150,-67.150,-66.967,-66.967) |
geographic |
Langmuir |
geographic_facet |
Langmuir |
genre |
EISCAT |
genre_facet |
EISCAT |
op_relation |
Journal Of Atmospheric And Solar-terrestrial Physics, 2015, 135, pp. 50-63 (14) 1364-6826 http://www.sciencedirect.com/science/article/pii/S1364682615300705 http://hdl.handle.net/2381/36451 doi:10.1016/j.jastp.2015.10.009 S1364682615300705 |
op_rights |
Copyright © 2015 Elsevier Ltd. All rights reserved. This manuscript version is made available after the end of the embargo period under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ |
op_rightsnorm |
CC-BY-NC-ND |
op_doi |
https://doi.org/10.1016/j.jastp.2015.10.009 |
container_title |
Journal of Atmospheric and Solar-Terrestrial Physics |
container_volume |
135 |
container_start_page |
50 |
op_container_end_page |
63 |
_version_ |
1766400491457085440 |
spelling |
ftleicester:oai:lra.le.ac.uk:2381/36451 2023-05-15T16:04:51+02:00 Modification of the high latitude ionosphere F region by X-mode powerful HF radio waves: Experimental results from multi-instrument diagnostics Blagoveshchenskaya, N. F. Borisova, T. D. Yeoman, Timothy Kenneth Haggstrom, I. Kalishin, A. S. 2016-01-28T12:55:12Z http://www.sciencedirect.com/science/article/pii/S1364682615300705 http://hdl.handle.net/2381/36451 https://doi.org/10.1016/j.jastp.2015.10.009 en eng Elsevier Journal Of Atmospheric And Solar-terrestrial Physics, 2015, 135, pp. 50-63 (14) 1364-6826 http://www.sciencedirect.com/science/article/pii/S1364682615300705 http://hdl.handle.net/2381/36451 doi:10.1016/j.jastp.2015.10.009 S1364682615300705 Copyright © 2015 Elsevier Ltd. All rights reserved. This manuscript version is made available after the end of the embargo period under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ CC-BY-NC-ND Science & Technology Physical Sciences Geochemistry & Geophysics Meteorology & Atmospheric Sciences Ionosphere (active experiments) Radio Science (nonlinear phenomena) STIMULATED BRILLOUIN-SCATTERING ION GYROHARMONIC STRUCTURES ASPECT ANGLE DEPENDENCE HEATING EXPERIMENTS LANGMUIR TURBULENCE MAGNETIC ZENITH ELECTROMAGNETIC EMISSIONS INCOHERENT BACKSCATTER ENHANCED PLASMA INDUCED AIRGLOW Journal Article Article;Journal 2016 ftleicester https://doi.org/10.1016/j.jastp.2015.10.009 2019-03-22T20:21:21Z The file associated with this record is under a 24-month embargo from publication in accordance with the publisher's self-archiving policy. The full text may be available through the publisher links provided above. We present experimental results concentrating on a variety of phenomena in the high latitude ionosphere F2 layer induced by an extraordinary (X-mode) HF pump wave at high heater frequencies (f[Subscript: H]=6.2–8.0 MHz), depending on the pump frequency proximity to the ordinary and extraordinary mode critical frequencies, foF2 and fxF2. The experiments were carried out at the EISCAT HF heating facility with an effective radiated power of 450–650 MW in October 2012 and October–November 2013. Their distinctive feature is a wide diapason of critical frequency changes, when the f[Subscript: H]/foF2 ratio was varied through a wide range from 0.9 to 1.35. It provides both a proper comparison of X-mode HF-induced phenomena excited under different ratios of f[Subscript: H]/foF2 and an estimation of the frequency range above foF2 in which such X-mode phenomena are still possible. It was shown that the HF-enhanced ion and plasma lines are excited above foF2 when the HF pump frequency is lying in range between the foF2 and fxF2, foF2≤f[Subscript: H]≤fxF2, whereas small-scale field-aligned irregularities continued to be generated even when f[Subscript: H] exceeded fxF2 by up to 1 MHz and an X-polarized pump wave cannot be reflected from the ionosphere. Another parameter of importance is the magnetic zenith effect (HF beam/radar angle direction) which is typical for X-mode phenomena under f[Subscript: H]/foF2 >1 as well as f[Subscript: H]/foF2 ≤1. We have shown for the first time that an X-mode HF pump wave is able to generate strong narrowband spectral components in the SEE spectra (within 1 kHz of pump frequency) in the ionosphere F region, which were recorded at distance of 1200 km from the HF heating facility. The observed spectral lines can be associated with the ion acoustic, electrostatic ion cyclotron, and electrostatic ion cyclotron harmonic waves (otherwise known as neutralized ion Bernstein waves). The comparison between the O- and X-mode SEE spectra recorded at distance far from HF heating facility clearly demonstrated that variety of the narrowband spectral structures were only observed under X-mode HF pumping. The potential generation mechanisms of the different narrowband spectral components are discussed. Peer-reviewed Post-print Article in Journal/Newspaper EISCAT University of Leicester: Leicester Research Archive (LRA) Langmuir ENVELOPE(-67.150,-67.150,-66.967,-66.967) Journal of Atmospheric and Solar-Terrestrial Physics 135 50 63 |