| アイテムタイプ |
学術雑誌論文 = Journal Article(1) |
| 公開日 |
2023-12-08 |
| 資源タイプ |
|
|
資源タイプ識別子 |
http://purl.org/coar/resource_type/c_6501 |
|
資源タイプ |
journal article |
| タイトル |
|
|
タイトル |
Ultra Low Frequency Modulation of Energetic Electron Precipitation in the D-Region Ionosphere in a Magnetically Quiet Time Using OCTAVE Very Low Frequency and Low Frequency (VLF/LF) Observations |
|
言語 |
en |
| 言語 |
|
|
言語 |
eng |
| 著者 |
Tanaka, Kentaro
Ohya, Hiroyo
Tsuchiya, Fuminori
Nozaki, Kenro
寺本, 万里子
Shiokawa, Kazuo
Miyoshi, Yoshizumi
Connors, Martin
Nakata, Hiroyuki
|
| 抄録 |
|
|
内容記述タイプ |
Abstract |
|
内容記述 |
There are several studies of energetic electron precipitation (EEP) modulated by ultra low frequency (ULF) during substorms, although there are few in geomagnetically quiet times. At present, it is not clear how often such quiet time EEP occurs and the mechanism involved. In this study, we investigate EEP modulated by ULF (,5 Hz) from Observation of CondiTion of ionized Atmosphere by VLF Experiment (OCTAVE) very low frequency (VLF; 3 kHz to 30 kHz) and low frequency (LF; 30 kHz to 300 kHz) observations in geomagnetically quiet times. The OCTAVE is a worldwide network of VLF/LF signals that we established. The VLF/LF transmitter signals from four transmitters (NLK, NDK, WWVB, and NAA) in the USA were received at Athabasca (ATH; 54.78N, 113.38E, L . 4.3), Canada. There were oscillations in amplitude on the NDK-ATH and NLK-ATH paths with periods of 240 s and 270 s during magnetically quiet times from 11:20 Universal Time (UT) to 11:40 UT on October 9, 2017, respectively. The amplitudes of the VLF/LF variations were 3 dB and 1 dB on the NDKATH and NLK-ATH paths, respectively. Based on the wave–hop method, reflection height varied by ~4.3 km during the VLF/LF oscillations, indicating that the electron density in the D-region ionosphere increased by ~680 cm_3 (110%) at a 91 km height. The H component of ground-based magnetic field data at ATH and low latitudes showed the geomagnetic Pi2 pulsations with a similar period to that in the VLF/LF signals. The main cause of the VLF/LF oscillations could be ULF-modulated EEP due to the lowering of mirror points. |
|
言語 |
en |
| 書誌情報 |
en : URSI Radio Science Letters
巻 4,
発行日 2022
|
| 出版社 |
|
|
出版者 |
Union of Radio Science |
| DOI |
|
|
|
識別子タイプ |
DOI |
|
|
関連識別子 |
https://doi.org/10.46620/22-0049 |
| URI |
|
|
|
識別子タイプ |
URI |
|
|
関連識別子 |
https://www.ursi.org/publications.php?highlight=rs |
| 出版タイプ |
|
|
出版タイプ |
VoR |
|
出版タイプResource |
http://purl.org/coar/version/c_970fb48d4fbd8a85 |
| 査読の有無 |
|
|
値 |
yes |
LaSEINE-2022_024.pdf (589 KB)
