Simultaneous generation of large‐scale density irregularities and geomagnetic pulsations via filamentation instability

Kuo, Spencer; Cheng, Wei Te; Cohen, Joel A.; Pradipta, Rezy; Lee, M. C.; Snyder, Arnold

doi:10.1029/2009gl037942

Cited by 8 publications

(8 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At the same time, our mechanism is significantly different from the mechanism of generation of geomagnetic fluctuations directly within the antenna pattern of the heater, which is related with the development of the filamentation instability. This mechanism was considered in [35][36][37][38]). …”

Section: Drag Of Charged Particles By the Wavementioning

confidence: 99%

Geomagnetic Pulsation Amplitude and Spectrum Variations Accompanying the Ionospheric Heating by High-Power Radio waves from the Sura Facility

Черногор

Frolov

2014

Radiophys Quantum El

View full text Add to dashboard Cite

Aperiodic and quasiperiodic variations in the geomagnetic pulsation amplitude in a range of periods from 40 to 1000 s, which accompany the quasicontinuous and periodic impact on the ionospheric plasma by high-power radio waves from the SURA facility near Nizhny Novgorod (Russia) were recorded near Kharkov (Ukraine) using a magnetometer-fluxmeter. The main parameters of aperiodic and quasiperiodic disturbances of the geomagnetic field are determined. The mechanisms for generation and propagation of detected disturbances are discussed.

show abstract

Section: Drag Of Charged Particles By the Wavementioning

confidence: 99%

Geomagnetic Pulsation Amplitude and Spectrum Variations Accompanying the Ionospheric Heating by High-Power Radio waves from the Sura Facility

Черногор

Frolov

2014

Radiophys Quantum El

View full text Add to dashboard Cite

show abstract

“…[16] The presence of medium-to large-scale density irregularities (i.e., a few tens of meters to a few kilometers) in the background ionosphere [Fejer, 1979] can scatter the ionosonde signals out of the transmit beam to reduce or even eliminate backward scattering or reflection [Kuo et al, 2009]. There are several mechanisms which can generate density irregularities by the HF heaters [Kuo and Schmidt, 1983;Lee and Kuo, 1983].…”

Section: Background Conditions and Experimentsmentioning

confidence: 99%

Observation and theory of whistler wave generation by high‐power HF waves

et al. 2013

Self Cite

View full text Add to dashboard Cite

[1] Summer midnight and afternoon VLF wave generation comparison experiments were conducted on 25 July and 27 July 2011, respectively, using two CW HF X-mode waves with 11 VLF frequency differences from 2 to 21.5 kHz. The background magnetic variations were at comparable levels. During the afternoon experiment, the D region absorption was significant and increasing. The number of the ionogram echoes decreased during the afternoon experiment. VLF signals were detected from 2 to 7.6 kHz in both experiments, showing an inverse frequency dependence of intensity, although signal intensity (except at 5.5 kHz) detected during the midnight experiment was stronger than the corresponding afternoon intensity before observing a decrease of the number of ionogram echoes. However, VLF signals from 11.5 to 21.5 (except at 19.6 kHz) were also generated in the afternoon experiment concurrent with a decrease of the O-mode ionosonde echoes from 2 to 4 MHz. The concurrence of a decrease of the afternoon ionogram echoes, the unexpected generation of VLF waves at higher frequencies, and the increasing D region absorption throughout the experiment may be explained by the generation of large-scale density irregularities, which scatter the ionosonde signals as well as couple with the modulated electrojet to generate whistler waves. A theoretical formulation of the coupling mechanism for the whistler wave generation is presented.

show abstract

“…Thermal self-focusing instability is responsible for the generation of artificial spread F in ionograms in the ionospheric heating experiments [Kuo and Djuth, 1988]. Another candidate mechanism for these large-scale FAIs generation is thermal filamentation instability, which indicates that the HF wave polarization has important effects [Kuo and Schmidt, 1983;Lee et al, 1998;Kuo et al, 2009].…”

Section: Introductionmentioning

confidence: 99%

A numerical study of large‐scale ionospheric modulation due to the thermal process by powerful wave heating

Zhou

Wang

et al. 2016

JGR Space Physics

View full text Add to dashboard Cite

We present a three‐dimensional numerical model of large‐scale ionospheric electron density and temperature modulation by powerful electromagnetic waves by incorporating the transport equations and the three‐dimensional ray‐tracing algorithm. Based on this numerical model, the changes of ionospheric electron density and temperature at nighttime are investigated. The simulation results present (1) the ionospheric electron temperature enhancement due to the energy absorption; (2) the ionospheric electron density depletion at the reflection region and enhancement at the upper/lower region along the field line due to the thermal pressure; and (3) large‐scale field‐aligned irregularities (FAIs) due to the thermal self‐focusing instability with transverse scale of ~10 km. The results are quantitatively consistent with the previous theoretical predictions and experimental observations, which indicate that the thermal processes play an important role in the ionospheric electron density/temperature modulation and large‐scale FAI generation.

show abstract

Simultaneous generation of large‐scale density irregularities and geomagnetic pulsations via filamentation instability

Cited by 8 publications

References 13 publications

Geomagnetic Pulsation Amplitude and Spectrum Variations Accompanying the Ionospheric Heating by High-Power Radio waves from the Sura Facility

Geomagnetic Pulsation Amplitude and Spectrum Variations Accompanying the Ionospheric Heating by High-Power Radio waves from the Sura Facility

Observation and theory of whistler wave generation by high‐power HF waves

A numerical study of large‐scale ionospheric modulation due to the thermal process by powerful wave heating

Contact Info

Product

Resources

About