HAARP-induced Ionospheric Ducts Gennady Milikh, University of Maryland in collaboration with: Dennis Papadopoulos, Chia-Lee Chang, BAE systems Evgeny Mishin,

HAARP-induced HAARP-induced Ionospheric DuctsIonospheric DuctsGennady Milikh, Gennady Milikh, University of University of

Maryland Maryland

in collaboration with: Dennis Papadopoulos, in collaboration with: Dennis Papadopoulos, Chia-Lee Chang, Chia-Lee Chang, BAEBAE systems systems

Evgeny Mishin,Evgeny Mishin, AFRL/RVBXI, AFRL/RVBXI, Hanscom AFBHanscom AFBMichel ParrotMichel Parrot, LPCE/CNRS, France, LPCE/CNRS, France

Joe HubaJoe Huba, NRL, NRLAndrei DemekhovAndrei Demekhov, IAP, N-Novgorod, Russia, IAP, N-Novgorod, Russia

Conference on Dynamical Processes in Space Plasma, Israel, April, 2010

MotivationMotivation

• Naturally induced field aligned irregularities of the plasma density exhibit enhanced refractive indices and act as ducts that guide waves in the whistler range between the two hemispheres.

• HF heating of the ionosphere creates density perturbations that may propagate into the plasmasphere, thus produce artificial ducts.

ObjectivesObjectives

•To present the observations of the density perturbations caused by the HF-heating of the ionosphere by HAARP and detected by Demeter and DMSP satellites.

•To check the observations against a model of the artificial ducts due to HF-heating of the ionosphere.

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04/24/07f=3.2 MHzO-mode0.1 HzMagn. Zen.No electrojet

Demeter observations of the daytime artificial ducts

10/16/09f=5.1 MHz, O-modeCW, Magn. Zen.

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Kodiak radar diagnostics

HF-heating

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Daytime Measurements (summarizing)

Daytime artificial ducts are narrow (the width in N-S direction is under 100 km), and relatively weak (Ni,e and Ti,e perturbations are under 10%). Thus they can be detected only from a close overfly.

The artificial ducts required a strong HF-heating which produces the ionospheric perturbations, such as observed by Kodiak. To generate such perturbations the heating frequency should be close to MUF.

99

04/24/07f=3.2 MHzO-mode0.1 HzMagn. Zen.No electrojet

Demeter observations of the nighttime artificial ducts

10/21/09f=2.8 MHz, O-modeCW, Magn. Zen.

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Nighttime Measurements (summarizing)

• Nighttime artificial ducts broader than daytime (the width reaches 200 km), and Ni,e and Ti,e perturbations reach 80%. Detectable even at few hundred km distances from the HAARP MZ.

• Outflow of O+ ions pushes H+ and He+ upward – artificial polar wind.

The model of artificial ducts in the The model of artificial ducts in the ionosphereionosphere

•It is based on the SAMI2 model of the ionosphere [Huba, et al., 2000] which describes evolution of the ionospheric plasma confined by a bunch of the geomagnetic field lines.

•The SAMI2 model was modified, namely a flexible local source of the electron HF-heating was introduced in the form of the localized heating rate per electron:

4/ 2 10 ( / )eq P Vn K s

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Model Validation

Validation of the numerical model of ductsby comparison with two well documented experiments:

The first experiment was conducted at the EISCAT facility and diagnosed by the EISCAT Incoherent Scatter Radar, which measured the vertical profiles of the electron and ion temperature between 150 - 600 km.

The second experiment was conducted at the SURA facility, and used DEMETER satellite as a diagnostic tool to measure the ion density along the overflying satellite orbit close to the magnetic zenith of the HF-heater.

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EISCAT EXPERIMENT

EISCAT HF facility is located near Tromso, Norway (69ooN, 19oE)

Experiments conducted on 10/7/99 [Rietveld et al., JGR, 2003]

Heater operated at 4.5 MHz, ERP=205 MW under quiet ionospheric conditions.

Major diagnostic tool: UHF ISR.

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Comparison with the EISCAT experiment (model has been adjusted)

The absorption efficiencies=0.16, 0.32 and 0.64.

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SURA EXPERIMENT

SURA HF facility located near Nizny Novgorod, Russia (56ooN, 46oE).

Experiment conducted on 05/01/06 [Frolov et al., Radiophys. @ Quantum Electronics, 2008] under quiet ionospheric conditions.

The heater operated at 4.3 MHz, O-mode, magnetic zenith, ERP=80 MW.

Ground-based diagnostics was provided by ionosonde.

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Comparison with the SURA experiment

Absorption efficiencies=0.14 (blue) and 0.25 (red), crosses - observations.

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In summary, the modified model of ducts reproduces observations with high accuracy, which establishes it as a key tool for the study of the artificial ionospheric modifications.

2020

Demeter observations of the nighttime artificial ducts

02/12/10 f=2.8 MHz, O-mode, CW, MZ

Focusing of HF waves by ducts

The strong signal was detected between 6:30:37 – 6:30:47 shown by arrows

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Theory of focusing of HF waves by ducts

0oNeΔN

2ω

2eω

21Δn

rρ2drdznΔc

ωiexpc2π

ωoiφAeE

i

i.e. forming a focusing lens

Expanding n and r by powers of 2 we obtain the focusing distance

km50~ ifkm400300~o/NeΔNΔz

2ρoz

1

dzoNeΔN

2ρ

22ω

2eω

oz

1000~2

oNeΔN

2cΔz f2

E/A

Lens

Magnification:

ConclusionsConclusions• Artificial ducts due to the ionospheric heating was

detected by the Demeter satellite during daytime & nighttime.

• Modified SAMI2 model provides quantitative predictions of the ducts.

• HF focusing by ducts propagation was detected. A HF focusing by ducts propagation was detected. A theoretical model of HF-focusing was developed.theoretical model of HF-focusing was developed.