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HEATING expands the mind. EISCAT training course. The past G. Marconi (1874 -1937) Nobel Prize 1909. There had to be a reflecting layer in order to explain his trans-Atlantic radio wave connection. Reflecting layer at 100-200 km altitude (the ionosphere). Radio Sender. Earth. Receiver.
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HEATINGexpands the mind EISCAT training course
The past G. Marconi (1874 -1937) Nobel Prize 1909 There had to be a reflecting layer in order to explain his trans-Atlantic radio wave connection. Reflecting layer at 100-200 km altitude (the ionosphere) Radio Sender Earth Receiver
The past N. Tesla (1856-1943) Tesla developed high-frequency high-power generators
The past At the same time as Marconi, Tesla wanted to transmit energy as well as information using wireless radio waves. He built a transmission tower for this pupose. However, his work had little to do with modern ionospheric research.
The past Geometry of the Luxembourg effect (Tellegen, 1933)
EISCAT consists of much more than just radars. It possesses the world‘s largest high-frequency (HF) ionospheric modifi-cation facility, called HEATING or simply the HEATER. Built by the Max-Planck-Society in the late 1970s, it passed to EISCAT in 1993. EISCAT mainland
A geographic overview of the EISCAT radar, HEATING & SPEAR HF facilities and CUTLASS coherent scatter radars
The Heating facility at Tromsø Control Antenna 1 Transmitter Antenna 2 Antenna 3
Coax Only 50 km of home-made aluminium RF coaxial transmission lines with mechanical switches
2 Antennas give a broad beam Beam forming 4 Antennas give a narrower beam with more power in the forward direction and less power in all other directions. Effective Radiated Power = Radiated power Antenna gain At Heating: 300 MW = 1.1 MW 270 for low gain antennas 1.2 GW = 1200 MW = 1.1 MW 1100 for high gain antenna
1970: Platteville, Colorado • 1975: SURA (Nizhni Novgorod), Russia • ~1980: Arecibo (Puerto Rico), • Tromsø (Norway), HIPAS (Alaska) • 1995: HAARP (Alaska) • 2003: SPEAR (Svalbard) World overview
A comparison HEATINGSPEARHAARP (final) Power (MW): 1.1 0.192 3.3 Antenna 24 and 30 16 & 22 30Gain (dB): ERP (MW): 300 & 1200 7.6 & 30 3600 Freq. (MHZ): 3.9-5.4 & 5.4-8 2-3 & 4-6 2.8-10 Polarisation: O & X O & X O & X Beam only north-south any anySteering: relatively slowfast fast Diagnostics: KST ESR ? CUTLASS CUTLASS KODIAK Dynasonde ? Digisonde
The ionosphere Fc = 8.98*sqrt(Ne) for O-mode Fc = 8.98*sqrt(Ne) + 0.5*Be/m for X-mode
A comparison of frequency range and effective radiated power of different facilities 1GW 100 MW SPEAR 10 MW
Why do we need the HEATING facility? • Why?: HF facilities are the only true active experiments in the ionosphere because the plasma may be temporarily modified under user control. • Operations: ~200 hours per year (1 year=8760 hours), mostly in user-defined campaign mode. • Experiments can be divided into 2 groups: • Plasma physics investigations: the ionosphere is used as a laboratory to study wave-plasma turbulence and instabilities. • Geophysical investigations: ionospheric, atmospheric or magnetospheric research is undertaken.
The Incoherent Scatter RadarSpectra with Ion and Plasma lines corresponding to ion-acoustic waves and Langmuir waves Langmuir turbulence, the parametric decay instability: e/m pump(0 ,0) Langmuir(0 -ia,-k) + IonAcoustic(ia ,k) Langmuir(0 -ia,-k) Langmuir(0 -2ia,k) + IonAcoustic (ia,-2k) The component of the pump electric field parallel to the Earth's magnetic field is what matters. Thermal resonance instability: e/m pump + field-aligned electron density striation electrostatic wave (UH) Upper hybrid (UH) resonance condition: 02 = p2 + e2 The component of the pump electric field perpendicular to the Earth's magnetic field is what matters.
PLASMA TURBULENCE 12 Nov 2001 5.423 MHz ERP = 830 MW O-mode UHF ion line spectra HF on HF off
PLASMA TURBULENCE The UHF radar observes HF pump-induced plasma turbulence 5.423 MHz ERP = 1.1 GW O-mode
PLASMA TURBULENCE Z-mode penetration of the ionosphere
HF pump-induced magnetic field-aligned electron density irregularities (up to ~5%) causes coherent radar reflections and anomalous absorption (by scattering) of probing signals. Striations
Striations Amplitude of radio waves received from the satellite
Striations After HF pump off, the irregularities decay with time
HF induced E-region STARE backscatter (144 MHz) Tromsø
Artificially raised electron temperatures 16 Feb 1999 4.04 MHz ERP = 75 MW O-mode Heater on
HF pump-induced artificial optical emissions 16 Feb 1999 4.04 MHz ERP = 75 MWO-mode 17:40 HF on 17:44 HF off
HEATER and UHF beam swinging UHF zenith angle 7 Oct 1999 4.954 MHz ERP = 100 MW O-mode
ARTIFICIAL AURORA shifted onto magnetic field line Heater beam (vertical) Spitze direction Field aligned 21 Feb 1999 630 nm Start time: 17.07.50 UT Step=480 sec 4.04 MHz ERP = 75 MW O-mode
Stimulated Electromagnetic Emissions are weak radio waves produced in the ionosphere by HF pumping. They were originally discovered at HEATING. HF transmit frequency Gyroharmonic 1.38 MHz in F-layer
GYRO-HARMONIC Special effects appear for HF frequencies close to an electron gyro-harmonic. (~1.38 MHz in F-layer)
GYROHARMONIC 3 Nov 2000 ERP = 70 MW O-mode UHF Cutlass Artificial aurora 630 nm
VHF PMSE Artificial HF modulation of Polar Mesospheric Summer Echoes. VHF backscatter power reduces by >40 dB. 10 July 1999 5.423 MHz ERP = 630 MW X-mode HF off HF on
Satellite in the magnetosphere ULF ELF VLF waves Ionosphere DC current Conductivity modulation causes electrojet modulation, which acts as a huge natural antenna 100 km altitude 30 km diameter superimposed ac current 0.001-1 W ULF/ELF/VLF waves are radiated from the ionosphere Heating Tx: 0.2-1 GW HF waveis amplitude modulated and radiated VLF receiver
Very Low Frequency waves (kHz) Natural (lightning) and artificial (HEATING) ducted VLF waves resonate with trapped particles in the magnetosphere causing pitch angle scattering and precipitation.
Ultra Low Frequency waves (3 Hz) Field line tagging
Artificial Periodic Irregularities (API) The API technique was discovered at SURA and allows any HF pump and ionosonde to probe the ionosphere. API are formed by a standing wave due to interference between the upward radiated wave and its own reflection from the ionosphere. Measured parameters include: N(n), N(e), N(O-), vertical V(i), T(n), T(i) & T(e)
Further information EISCAT/HEATING www.eiscat.uit.no/heater.html HAARP www.haarp.alaska.edu HIPAS www.hipas.alaska.edu ARECIBO www.naic.edu SURA www.nirfi.sci-nnov.ru/english/index2e.html SPEAR www.ion.le.ac.uk/spear/