Solar flares detected by the new narrowband VLF receiver at SANAE IV

  • Hanna Dahlgren Space and Plasma Physics, Royal Institute of Technology
  • Torbjörn Sundberg Space and Plasma Physics, Royal Institute of Technology
  • Andrew B. Collier SANSA Space Science
  • Etienne Koen Plasma Physics, Royal Institute of Technology
  • Stephen Meyer SANSA Space Science
Keywords: ionosphere, VLF waves, solar flares, remote sensing, wave propagation

Abstract

A narrowband receiver was installed at the SANAE IV base in Antarctica to monitor specific very low frequency (VLF) radio signals from transmitters around the world. VLF waves propagating through the Earth–Ionosphere Waveguide are excellent probes of the varying properties of the lower region of the ionosphere. This paper describes the set-up of the narrowband system and demonstrates its capabilities with data from a set of solar flares on 08 February and 12 February 2010.

Author Biographies

Hanna Dahlgren, Space and Plasma Physics, Royal Institute of Technology
Department of Electrical and Computer Engineering and Center for Space Physics, Boston University
USA
Torbjörn Sundberg, Space and Plasma Physics, Royal Institute of Technology
Heliophysics Science Division, NASA Goddard Space Flight Center
USA
Andrew B. Collier, SANSA Space Science
University of KwaZulu-Natal
South Africa
Etienne Koen, Plasma Physics, Royal Institute of Technology
SANSA Space Science
South Africa
Stephen Meyer, SANSA Space Science
University of KwaZulu-Natal
South Africa

References

1. Thomson NR, Clilverd MA. Solar cycle changes in daytime VLF subionospheric attenuation. J Atmos Solar Terr Phys. 2000;62:601–608. doi:10.1016/S1364-6826(00)00026-2

2. Cummer SA, Inan US, Bell TF. Ionospheric D region remote sensing using VLF radio atmospherics. Radio Sci. 1998;33:1781–1792. doi:10.1029/98RS02381

3. Bickel JE, Ferguson JA, Stanley GV. Experimental observation of magnetic field effects on VLF propagation at night. Radio Sci. 1970;5:19–25. doi:10.1029/RS005i001p00019

4. Thomson NR. Experimental daytime VLF ionospheric parameters. J Atmos Terr Phys. 1993;55:173. doi:10.1016/0021-9169(93)90122-F

5. Collier AB, Hughes ARW. Digital VLF recording and analysis system for SANAE IV. S Afr J Sci. 2002;98(11/12):547–550.

6. Clilverd MA, Rodger CJ, Thomson NR, et al. Remote sensing space weather events: Antarctic–Arctic Radiation-belt (Dynamic) Deposition-VLF Atmospheric Research Konsortium network. Space Weather. 2009;7:15. doi:10.1029/2008SW000412

7. Dowden RL, Holzworth RH, Rodger CJ, et al. World-Wide Lightning Location Using VLF Propagation in the Earth–Ionosphere Waveguide. IEEE Antennas Propag Mag. 2008;50(5):40–60. doi:10.1109/MAP.2008.4674710

8. Barr R. A simple theoretical model of the diffraction of VLF electromagnetic waves by the Antarctic icecap. J Atmos Solar Terr Phys. 1992;54:1527–1533. doi:10.1016/0021-9169(92)90160-M

9. Wait JR. Electromagnetic waves in stratified media. Vol. 3 of International Series of Monographs on Electromagnetic Waves. New York: Pergamon Press; 1962.

10. Thomson NR. Experimental daytime VLF ionospheric parameters. J Atmos Terr Phys. 1993;55:173–184. doi:10.1016/0021-9169(93)90122-F

11. McRae WM, Thomson NR. VLF phase and amplitude: daytime ionospheric parameters. J Atmos Terr Phys. 2000;62:609–618. doi:10.1016/S1364-6826(00)00027-4

12. Deshpande SD, Subrahmanyam CV, Mitra AP. Ionospheric effects of solar flares – I. The statistical relationship between X-ray flares and SID’s. J Atmos Terr Phys. 1972;34:211–227. doi:10.1016/0021-9169(72)90165-1

13. McRae WM, Thomson NR. Solar flare induced ionospheric D-region enhancements from VLF phase and amplitude observations. J Atmos Terr Phys. 2004;66:77–87. doi:10.1016/j.jastp.2003.09.009

14. Thomson NR, Rodger CJ, Clilverd MA. Large solar flares and their ionospheric D-region enhancements. J Geophys Res. 2005;110:6306–6316. doi:10.1029/2005JA011008
Published
2011-09-06