1 / 26

Physics and Measurements of Stimulated Electromagnetic Emissions

Physics and Measurements of Stimulated Electromagnetic Emissions. Paul A. Bernhardt, Stan Briczinski Plasma Physics Division Naval Research Laboratory Washington, DC 20375 University of Maryland 8 November 2011. Studying the Ionosphere with Active Experiments.

norina
Download Presentation

Physics and Measurements of Stimulated Electromagnetic Emissions

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Physics and Measurements of Stimulated Electromagnetic Emissions Paul A. Bernhardt, Stan Briczinski Plasma Physics Division Naval Research Laboratory Washington, DC 20375 University of Maryland 8 November 2011

  2. Studying the Ionosphere with Active Experiments • Active Experiments with High Power Radio Waves • Frequency Range (2.6 to 10 MHz) • Global Distribution of HF Facilities • Physics of High Power Radio Waves • Density, Temperature, Composition, and Irregularities • Active Technique • Field Aligned Irregularity Glow with HF Excitation • Stimulated Electromagnetic Emissions (SEE) • Plasma Wave Generation and Propagation • Research Inspired by Uppsala University • Low Frequency • OAM HF Beam Interactions • Dissertation Defense

  3. The Ionosphere Described by NRL SAMI3 in 2010 • Ref.: Huba, Krall, Joyce, SAMI3, 2010 • Plasma Density: 103 to 106 cm-3 • F-Layer Electron Temp.: 500 to 3000 K (0.05 to 0.3 eV) • F-Layer O+ Ion Temp.: 500 to 2000 K • Magnetic Field Strength: B0 ≈ 28 10-6 T • Plasma Pressure Versus Magnetic Pressure b ≈ nkT/(B2/2m0) = 10-8 • Ion Collisions Versus Ion Gyro Orbits Wi ~ ni at 100 km Altitude

  4. Past, Current and Future HF Ionospheric Modification Facilities Jicamarca Arecibo Conjugate

  5. Stimulated Electromagnetic Emissions,Radar Backscatter, Enhanced Plasma Waves and Artificial Aurora HF Receiver HF Receiver UHF Radar Camera F-Region Ionosphere HF Radar HAARP Transmitter

  6. Plasma Physics of Ionospheric Modification withHigh Power Radio Waves Electron Temperature Elevation Plasma Pressure and Density Changes VLF Ducts and Conductivity Modification VLF Waveguides and VLF Generation Plasma Irregularity Formation Enhanced Radar Scatter Plasma Line High Power Electromagnetic Wave Beam Ion Line Electrostatic Wave Generation Mode Conversion Stimulated Electro- magnetic Emissions Low Frequency Waves Electron Acceleration Artificial Aurora Parametric Decay and Strong Turbulence High Frequency Waves

  7. HF Antenna for Receiving Stimulated Electromagnetic Emissions from HAARP

  8. Real Time Display of Stimulated Electromagnetic Emissions near HAARP with the MARK-IID Receiver

  9. ES and EM Wave Generation -10 -20 -30 -40 -50 -60 Pump DM In Situ Source: Upper Hybrid Waves Relative Power (dB) UM 2DM In Situ Source: Electron Bernstein Modes 3DM BUM 4.10 4.15 4.20 4.25 4.30 Frequency (MHz) Loss Parametric Decay High Power EM orESWave EM Pump Wave Low Frequency ESWave Optional Mode Conversion Loss Possible Mode Conversion ? High Frequency EMorESWave Low Frequency EMWave Optional Mode Conversion Loss Received EMWave

  10. HAARP HF Transmitter Array 2.6 to 10 MHz, Up to 3.6 GW Effective Radiated Power

  11. Heater Power Beam Angle Sweeping Vertical (28o , 22o) (28o, 202o) Magnetic Zenith IA IA & EIC I: Vertical beam (0o,0o) II: Zenith beam (14o ,202o) • Norin et al., 2009 observed the IA emission lines f1 and f2 due to Simulated Brillouin Scatter; • Bernhardt et al.,2009 observed IA lines f1 and 2010 observed IA line f1 and EIC lines f3 ; • Bernhardt, P. A., C. A. Selcher, and S. Kowtha (2011), Electron and ion Bernstein waves excited in the ionosphere by high power EM waves at the second harmonic of the electron cyclotron frequency, Geophys. Res. Lett., 38, L19107, doi:10.1029/2011GL049390. • The experiment conducted at HAARP in July, 2010 aims to look more thoroughly at a broader range of heater beam angle effects on IA and EIC waves generated by MSBS (Fu, Scales, Bernhardt 2011).

  12. Generalized MSBS matching conditions -f4 -f3 -f2 -f1 Reflection Upper hybrid [Bernhardt , 2009 ] f1- IA at reflection region; f2- IA at upper hybrid; f3- EIC at reflection region; f4- EIC at upper hybrid;

  13. Stimulated Brillouin Scatter with Ion Acoustic Wave Generation is Simple IA1 B EM1 EM2 SBS-1 -180 Hz -120 Hz 120 Hz 180 Hz q = 0 fIA1 SBS-1 Pump

  14. Brillouin Scattering of the 4.5 MHzHAARP Vertical Beam in the Ionosphere B

  15. SBS with EIC Generation Yields Ion Mass mi = e B/fEIC = m[O+] fIA-1 B q fEIC-1 -180 Hz -120 Hz 120 Hz 180 Hz Offset Frequency (Hz) Radio Beam Angel with B (q) 111.1 Azimuth 16.3 Zenith fIA-1 fEIC-1

  16. Set II : Experimental Results for 4.1 MHz, O-mode Full Power, UT 04:15:00-04:60:00,07/22/2010(Haiyang Fu, Virginia Tech) f1=10~12 Hz; f2=24~26 Hz; f3=50~52 Hz; f4=70~72 Hz; • The IA lines f1=10~12 Hz is stronger close to the magnetic zenith • The IA lines f2=24~26 Hz appears for ZA=28o, AZ=202o • The EIC lines f3=50~52 appears for ZA=28o, AZ=202o • The newly observed f4=70~72 appears for ZA=28o, AZ=202o

  17. Stimulated Ion Bernstein (SIB) Generation by Tuning to the Second Electron Gyro Frequency IB1 IB2 IB3 EM0 EB0 FAI EB1 EB2 EB3 FAI FAI FAI EM1 EM2 EM3 SIB2 SIB3 SIB1

  18. Stimulated Ion Bernstein Waves with f0 = 2 fce • HF Tuned to 2nd Electron Cyclotron Harmonic • Ion Cyclotron Frequency = 55 Hz • Dropout of Ion Cyclotron Mode • Constant Amplitudes for Ion Bernstein Modes • Observed at All Pointing Angles • Search for Narrowband Ground ELF Signal

  19. Direct ULF Generation • Process • HAARP 3.6 MW HF transmitter • High Gain Phased Array Antenna • 12 x 15 Dipoles Each Excited by 20 kW • Phased to Tilt HF Beam Greater than 20 Degrees from B • Frequency Tuned Away from Gyro Harmonic (4.2 MHz) • Decay of Pump Wave • Electrostatic Ion Cyclotron Wave • Downshifted EM Wave • Coupling of EIC wave to ULF EM Mode on Field Aligned Irregularities • Detection with Ground Receivers • UFL Receiver Tuned to About 48 Hz • HF Receiver Tuned to 4.2 MHz with 250 kHz BW • Results • EIC Mode Second Strongest Produced • Strong Dependence of HF Beam Orientation

  20. Stimulated ULF and HF Electromagnetic Emissions with HAARP F-Region Ionosphere ULF Receiver HF Receiver HAARP Transmitter

  21. Antenna Gain (dB) HAARP Array Generates a Hollow Beam

  22. HF Twisted Beam Altitude (km) Layer 1 Layer 2 Frequency (MHz) Artificial Ionospheric Layers Created by the HAARP Transmitter • Objectives • Form Stable Plasma Layer • Open Artificial Propagation Path • Progress • Demonstrated Twisted Beam • Formed Layer Lasting 5 Minutes • 4th Harmonic Resonance • Cyclotron Resonance Theory

  23. 25 March 2011 00:51:30 UT 25 March 2011 00:53:00 UT SEE Near the 4th Gyro Harmonic and Artificial Layers Layer Produced for 4.5 Minutes

  24. 26 August 2011 SEE 03:32 UT -1 0 1 2 3 4 Seconds +50 kHz 3.2 MHz -50 kHz 03:32:00 -100 kHz

  25. 27 August 2011 SEE00:04 UT +300 kHz +200 kHz +100 kHz 6.1 MHz 00:04:00 -100 kHz -200 kHz -300 kHz 0 1 2 3 4 5 6 Seconds

  26. HF SEE Receiver Use Conclusions Simple New Experiments for HAARP 4th Gyro Harmonic Heating with Twisted Beam Broad Upshifted Maximum and Ion Bernstein Waves in SEE Obtained with the Mark II-D Receivers Long Lasting Artificial Plasma Layers at Fixed Altitude Coordinated Receiver Observations HF SEE Modes Measured with the Mark II-D Receivers ULF Ground Modes Acknowledgments NRL Support by Geoff San Antonio and Serafin Rodriquez MIT Lincoln Support by Scott Coutts and Matthew Morris Future Work – Plasma Science Instruments in Space HF Receiver Langmuir Probe Magnetometer

More Related