Thermospheric neutral temperatures derived from charge-exchange produced N 2 + Meinel (1,0) rotational distributions
Thermalized rotational distributions of neutral and ionized N 2 and O 2 have long been used to determine neutral temperatures ( T n ) during auroral conditions. In both bright E-region (≲150 km) auroras, and in higher-altitude auroras, spectral distributions of molecular emissions employe...
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ftdoajarticles:oai:doaj.org/article:aa514b3512254bbcb14d6431a4c5f65d 2023-05-15T18:29:51+02:00 Thermospheric neutral temperatures derived from charge-exchange produced N 2 + Meinel (1,0) rotational distributions C. K. Mutiso M. D. Zettergren J. M. Hughes G. G. Sivjee 2013-03-01T00:00:00Z https://doi.org/10.5194/angeo-31-463-2013 https://doaj.org/article/aa514b3512254bbcb14d6431a4c5f65d EN eng Copernicus Publications https://www.ann-geophys.net/31/463/2013/angeo-31-463-2013.pdf https://doaj.org/toc/0992-7689 https://doaj.org/toc/1432-0576 doi:10.5194/angeo-31-463-2013 0992-7689 1432-0576 https://doaj.org/article/aa514b3512254bbcb14d6431a4c5f65d Annales Geophysicae, Vol 31, Pp 463-471 (2013) Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 article 2013 ftdoajarticles https://doi.org/10.5194/angeo-31-463-2013 2022-12-31T00:28:58Z Thermalized rotational distributions of neutral and ionized N 2 and O 2 have long been used to determine neutral temperatures ( T n ) during auroral conditions. In both bright E-region (≲150 km) auroras, and in higher-altitude auroras, spectral distributions of molecular emissions employed to determine T n in the E-region cannot likewise be used to obtain T n in the F-region. Nevertheless, charge-exchange reactions between high-altitude (≳130 km) species provide an exception to this situation. In particular, the charge-exchange reaction O + ( 2 D) + N 2 (X) → N + 2 (A 2 Π u , ν' = 1 + O( 3 P) yields thermalized N 2 + Meinel (1,0) emissions, which, albeit weak, can be used to derive neutral temperatures at altitudes of ~130 km and higher. In this work, we present N 2 + Meinel (1,0) rotational temperatures and brightnesses obtained at Svalbard, Norway, during various auroral conditions. We calculate T n at thermospheric altitudes of 130–180 km from thermalized rotational populations of N 2 + Meinel (1,0); these emissions are excited by soft electron (≲1 keV) impact and charge-exchange reactions. We model the contributions of the respective excitation mechanisms, and compare derived brightnesses to observations. The agreement between the two is good. Emission heights obtained from optical data, modeling, and ISR data are consistent. Obtaining thermospheric T n from charge-exchange excited N 2 + Meinel (1,0) emissions provides an additional means of remotely sensing the neutral atmosphere, although certain limiting conditions are necessary. These include precipitation of low-energy electrons, and a non-sunlit emitting layer. Article in Journal/Newspaper Svalbard Directory of Open Access Journals: DOAJ Articles Norway Svalbard Annales Geophysicae 31 3 463 471 |
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Directory of Open Access Journals: DOAJ Articles |
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language |
English |
topic |
Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 |
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Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 C. K. Mutiso M. D. Zettergren J. M. Hughes G. G. Sivjee Thermospheric neutral temperatures derived from charge-exchange produced N 2 + Meinel (1,0) rotational distributions |
topic_facet |
Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 |
description |
Thermalized rotational distributions of neutral and ionized N 2 and O 2 have long been used to determine neutral temperatures ( T n ) during auroral conditions. In both bright E-region (≲150 km) auroras, and in higher-altitude auroras, spectral distributions of molecular emissions employed to determine T n in the E-region cannot likewise be used to obtain T n in the F-region. Nevertheless, charge-exchange reactions between high-altitude (≳130 km) species provide an exception to this situation. In particular, the charge-exchange reaction O + ( 2 D) + N 2 (X) → N + 2 (A 2 Π u , ν' = 1 + O( 3 P) yields thermalized N 2 + Meinel (1,0) emissions, which, albeit weak, can be used to derive neutral temperatures at altitudes of ~130 km and higher. In this work, we present N 2 + Meinel (1,0) rotational temperatures and brightnesses obtained at Svalbard, Norway, during various auroral conditions. We calculate T n at thermospheric altitudes of 130–180 km from thermalized rotational populations of N 2 + Meinel (1,0); these emissions are excited by soft electron (≲1 keV) impact and charge-exchange reactions. We model the contributions of the respective excitation mechanisms, and compare derived brightnesses to observations. The agreement between the two is good. Emission heights obtained from optical data, modeling, and ISR data are consistent. Obtaining thermospheric T n from charge-exchange excited N 2 + Meinel (1,0) emissions provides an additional means of remotely sensing the neutral atmosphere, although certain limiting conditions are necessary. These include precipitation of low-energy electrons, and a non-sunlit emitting layer. |
format |
Article in Journal/Newspaper |
author |
C. K. Mutiso M. D. Zettergren J. M. Hughes G. G. Sivjee |
author_facet |
C. K. Mutiso M. D. Zettergren J. M. Hughes G. G. Sivjee |
author_sort |
C. K. Mutiso |
title |
Thermospheric neutral temperatures derived from charge-exchange produced N 2 + Meinel (1,0) rotational distributions |
title_short |
Thermospheric neutral temperatures derived from charge-exchange produced N 2 + Meinel (1,0) rotational distributions |
title_full |
Thermospheric neutral temperatures derived from charge-exchange produced N 2 + Meinel (1,0) rotational distributions |
title_fullStr |
Thermospheric neutral temperatures derived from charge-exchange produced N 2 + Meinel (1,0) rotational distributions |
title_full_unstemmed |
Thermospheric neutral temperatures derived from charge-exchange produced N 2 + Meinel (1,0) rotational distributions |
title_sort |
thermospheric neutral temperatures derived from charge-exchange produced n 2 + meinel (1,0) rotational distributions |
publisher |
Copernicus Publications |
publishDate |
2013 |
url |
https://doi.org/10.5194/angeo-31-463-2013 https://doaj.org/article/aa514b3512254bbcb14d6431a4c5f65d |
geographic |
Norway Svalbard |
geographic_facet |
Norway Svalbard |
genre |
Svalbard |
genre_facet |
Svalbard |
op_source |
Annales Geophysicae, Vol 31, Pp 463-471 (2013) |
op_relation |
https://www.ann-geophys.net/31/463/2013/angeo-31-463-2013.pdf https://doaj.org/toc/0992-7689 https://doaj.org/toc/1432-0576 doi:10.5194/angeo-31-463-2013 0992-7689 1432-0576 https://doaj.org/article/aa514b3512254bbcb14d6431a4c5f65d |
op_doi |
https://doi.org/10.5194/angeo-31-463-2013 |
container_title |
Annales Geophysicae |
container_volume |
31 |
container_issue |
3 |
container_start_page |
463 |
op_container_end_page |
471 |
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1766213273251741696 |