Auroral kilometric radiation/aurora correlation

Benson, Robert F.; Akasofu, S.‐I.

doi:10.1029/rs019i002p00527

Cited by 43 publications

(25 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, Benson and Calvert [1979]have observed AKR sources down to 2000 km with ISIS‐1 data. Using data from the same satellite, this minimum source region altitude for the source encounters is also confirmed in Figures 3–7 of Benson and Akasofu [1984] and Figures 27 and 28 of Benson [1985].…”

Section: Discussionsupporting

confidence: 58%

AKR‐like emissions observed at low altitude by the DEMETER satellite

Parrot¹,

Berthelier²

2012

J. Geophys. Res.

View full text Add to dashboard Cite

[1] This paper reports observations of Auroral Kilometric Radiation (AKR) by the low altitude satellite DEMETER (700 km) during the super magnetic storm of November 2004. AKR is generated along auroral field lines at altitudes above $3000 km and escapes from the Earth so that most observations have been made close to the source regions or at large distances from the Earth. However, EM waves with AKR-like frequency spectra detected by the low altitude EXOS-C satellite were interpreted by Oya et al. (1985) as AKR emissions propagating toward the Earth in the whistler mode. During the large magnetic storm of November 8-10, 2004, numerous events have been observed by DEMETER and, in one case, the emissions were recorded when DEMETER was flying over an intense aurora observed by the UVI (Ultra Violet Imager) of the POLAR spacecraft. During this event, density depletions have been observed at the satellite altitude. Similar AKR-like EM waves were also recorded by DEMETER at other times showing that these emissions are a common phenomenon at low altitudes in the auroral regions during periods of sustained magnetic activity.Citation: Parrot, M., and J.-J. Berthelier (2012), AKR-like emissions observed at low altitude by the DEMETER satellite,

show abstract

Section: Discussionsupporting

confidence: 58%

AKR‐like emissions observed at low altitude by the DEMETER satellite

Parrot¹,

Berthelier²

2012

J. Geophys. Res.

View full text Add to dashboard Cite

show abstract

“…Not only background cold plasma but also energetic electrons with anisotropic velocity distributions can control generation process of AKR. Locational correlation between AKR sources and discrete auroral arcs were well confirmed through observation studies based on ISIS 1 [ Benson and Akasofu , 1984], DE‐1 [ Huff et al , 1988], and Viking [ Pedersen et al , 1992]. Wu and Lee [1979] proposed that the free energy source of AKR is not a thermal anisotropy but a loss cone distribution with ∂ f /∂ v ⟂ > 0.…”

Section: Discussionmentioning

confidence: 86%

Seasonal and solar cycle variations of the vertical distribution of the occurrence probability of auroral kilometric radiation sources and of upflowing ion events

Kumamoto¹

2003

J. Geophys. Res.

View full text Add to dashboard Cite

[1] The seasonal and solar cycle variations of the vertical distribution of the occurrence probability of auroral kilometric radiation (AKR) sources and of upflowing ion (UFI) events have been investigated based on 13 years of plasma wave data and 8 years of energetic ion data observed by the Akebono satellite. In the summer polar region, the peak of the vertical distribution of the occurrence probability of AKR sources, identified by an intensity larger than À150 dB W/m 2 Hz, is at an altitude higher than 5000 km with a value of 10% in the solar maximum period and at an altitude of 5000-6000 km with a value of 40% in the solar minimum period. In the winter polar region, the peak altitudes and values are 4000-5000 km and 50% in the solar maximum period, and 4000 km and 60% in the solar minimum period, respectively. Based on the analysis of wave polarization data, intense R-X mode AKR is responsible for these variations. Furthermore, it has been also revealed that the vertical distribution of the occurrence probability of UFI events, identified by an ion velocity distribution function with a peak above 1 keV, also shows similar seasonal and solar cycle variations as the AKR sources. In both seasonal and solar cycle variations, the AKR and UFI occurrence probabilities decrease with increasing solar EUV ionization in the ionosphere. Therefore, ionospheric seasonal and solar cycle variations are inferred to be responsible for the AKR and UFI variations. As for the control mechanism, upwelling plasma from the ionosphere to the exosphere, up to an altitude of about 5000 km, are expected to change the temperature and density of the background plasma and control unstable conditions of plasma waves like ion acoustic waves and electrostatic ion cyclotron (EIC) waves, which generate the auroral particle acceleration regions.

show abstract

“…The signature of AKR on ISIS 1 ionograms has been described by Benson and Calvert [1979], Benson [1981], Calvert [1981a] and (in a comparison paper in this issue) Benson and Akasofu [1983]. ISIS 1 does not have the capability to make polarization measurements.…”

Section: Observationsmentioning

confidence: 99%

Ordinary mode auroral kilometric radiation, with harmonics, observed by ISIS 1

Benson

1984

Radio Science

Self Cite

View full text Add to dashboard Cite

ISIS 1 topside-sounder receiver observations that reveal examples of omode auroral kilometric radiation (AKR) are presented. They correspond to locations outside of the low density source region of intense AKR x-mode emission. The propagation modes are identified by comparing the natural radiation wave cutoffs with the local resonant and wave cutoff phenomena stimulated by the sounder transmitter. The o-mode AKR is the dominant emission in these regions of relatively high electron density, but it is considerably weaker than the intense x-mode AM observed to emanate from low density cavities above the auroral regions. In addition to the fundamental omode, 2nd and 3rd harmonic bands of radiation have also been detected.

show abstract

Auroral kilometric radiation/aurora correlation

Cited by 43 publications

References 32 publications

AKR‐like emissions observed at low altitude by the DEMETER satellite

AKR‐like emissions observed at low altitude by the DEMETER satellite

Seasonal and solar cycle variations of the vertical distribution of the occurrence probability of auroral kilometric radiation sources and of upflowing ion events

Ordinary mode auroral kilometric radiation, with harmonics, observed by ISIS 1

Contact Info

Product

Resources

About