Statistical Survey of Arase Satellite Data Sets in Conjunction With the Finnish Riometer Network

Thomas, Neethal; Kero, Antti; Miyoshi, Yoshizumi; Hyötylä, Miikka; Raita, Tero; Kasahara, Yoshiya; Shinohara, I.; Matsuda, Shoya; Nakamura, Satoko; Kasahara, Satoshi; Yokota, Shoichiro; Keika, K.; Hori, Tomoaki; Mitani, Takefumi; Takashima, Takeshi; Asamura, Kazushi; Kazama, Y.; Wang, Shiang‐Yu; Jun, Chae‐Woo; Higashio, Nana

doi:10.1029/2022ja030271

Cited by 2 publications

(4 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is probably the reason why the occurrence rates of CNA in Figures 5 and 6 are high from midnight to the dawn side. Thomas et al (2022) reported that during CNA events, the Arase satellite in the conjugate magnetosphere observed elevated electron flux in the medium energy range at 2-100 keV, and plasma wave activity in the whistler-mode frequency range (0.5-3 kHz) of the spectra.…”

Section: Discussionmentioning

confidence: 99%

“…During the main phase of the storm, the CNA pattern also exhibited oscillation in the Pc5 (2-7 mHz) range simultaneous with geomagnetic pulsations in the same frequency range. Recently, Thomas et al (2022) have statistically shown the dependence of the electron fluxes and plasma waves in the magnetosphere that cause CNA in the ionosphere, using conjugate observations between the Arase satellite and ground riometers over Finland.…”

Section: Introductionmentioning

confidence: 99%

“…Recently, Thomas et al. (2022) have statistically shown the dependence of the electron fluxes and plasma waves in the magnetosphere that cause CNA in the ionosphere, using conjugate observations between the Arase satellite and ground riometers over Finland.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Spatiotemporal Development of Cosmic Noise Absorption at Subauroral Latitudes Using Multipoint Ground‐Based Riometers

Kato,

Shiokawa,

Tanaka

et al. 2024

JGR Space Physics

Self Cite

View full text Add to dashboard Cite

Electron density enhancements in the ionospheric D‐region due to the precipitation of high‐energy electrons (>30 keV) have been measured as increases in cosmic radio noise absorption (CNA) using ground‐based riometers. CNA has been studied since the 1960s. However, there have been few studies of the spatiotemporal development of CNA at multi‐point ground stations distributed in longitude at subauroral latitudes, where plasma particles with a wide energy range are intermingled. In this study, we analyzed the longitudinal development of CNA steep increases using simultaneous riometer observations at six stations at subauroral latitudes in Canada, Alaska, Russia, and Iceland over 3 years from 2017 to 2020. The results revealed that the occurrence rate of steep increases in CNA was highest at midnight at 22‐08 magnetic local time (MLT), and lowest near dusk at 17–21 MLT. We also showed statistically that the CNA steep increases expanded eastward on the dawn side and westward on the dusk side. The CNA expansion velocity was slightly faster than the results of previous studies in the auroral zone. Correlation and superposed epoch analyses of CNA with solar wind and geomagnetic parameters revealed that CNA intensity was dependent on the Interplanetary Magnetic Field Bz, Interplanetary Electric Field Ey, SYM‐H index, and SME index. These results indicate that the CNA at subauroral latitudes is closely related to solar wind and geomagnetic activities, and its propagation characteristics correspond to the dynamics of high energy electrons in the inner magnetosphere.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Spatiotemporal Development of Cosmic Noise Absorption at Subauroral Latitudes Using Multipoint Ground‐Based Riometers

Kato,

Shiokawa,

Tanaka

et al. 2024

JGR Space Physics

Self Cite

View full text Add to dashboard Cite

show abstract

“…Behera et al (2016Behera et al ( , 2017 showed that CNAs were found to occur not only on the night side, but also on the noon and evening sides. Recently, Thomas et al (2022) have statistically shown using conjugate observations between the Arase satellite and ground riometers over Finland that during ground CNA events, Arase observed elevated electron flux in the medium energy range (2-100 keV) and plasma wave activity in the whistler-mode frequency range (0.5-3 kHz) of the spectra.…”

mentioning

confidence: 99%

Longitudinal Development of Cosmic Noise Absorption Based on Multipoint Observations at Subauroral Latitudes During Storm‐Time Substorms on 25–28 August 2018

Kato,

Shiokawa,

Tanaka

et al. 2024

JGR Space Physics

Self Cite

View full text Add to dashboard Cite

Enhancements in electron density in the D‐region ionosphere attributed to the precipitation of high‐energy electrons, have previously been inferred from increases in cosmic radio noise absorption (CNA) using ground‐based riometers. However, there have been few studies of CNA observations at multi‐point stations distributed in longitudes. Thus, the spatio‐temporal development of the global distribution of CNA is not well understood. In this study, we investigated the longitudinal extent of CNA using simultaneous riometer observations at six stations at subauroral latitudes in Canada, Alaska, Russia, and Iceland. These stations are located encircling the earth at ∼60° north magnetic latitudes. We have conducted simultaneous observations of CNA at these stations since October 2017. Here we focus on seven substorms during a geomagnetic storm 25–28 August 2018 and study the spatio‐temporal development of the global distribution of CNA during these substorms. For all seven substorms, some stations observed CNA enhancements after the substorm onsets. In five cases, the CNA enhancements started around midnight and expanded eastward. The other two cases show westward and anti‐sunward development of CNA. The eastward expansion of CNA indicates the eastward drift of high‐energy electrons, which is the source of the CNA, due to gradient and curvature drift in the geomagnetic field. The westward expansion of CNA may correspond to westward expansion of the substorm injection region due to dawn‐to‐dusk electric fields. These results indicate that spatio‐temporal development of CNA at subauroral latitudes corresponds to high energy electron drift in the inner magnetosphere.

show abstract

Statistical Survey of Arase Satellite Data Sets in Conjunction With the Finnish Riometer Network

Cited by 2 publications

References 56 publications

Spatiotemporal Development of Cosmic Noise Absorption at Subauroral Latitudes Using Multipoint Ground‐Based Riometers

Spatiotemporal Development of Cosmic Noise Absorption at Subauroral Latitudes Using Multipoint Ground‐Based Riometers

Longitudinal Development of Cosmic Noise Absorption Based on Multipoint Observations at Subauroral Latitudes During Storm‐Time Substorms on 25–28 August 2018

Contact Info

Product

Resources

About