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Intense plasma waves at and near the solar wind termination shock

Abstract

Plasma waves are a characteristic feature of shocks in plasmas, and are produced by non-thermal particle distributions that develop in the shock transition layer. The electric fields of these waves have a key role in dissipating energy in the shock and driving the particle distributions back towards thermal equilibrium1. Here we report the detection of intense plasma-wave electric fields at the solar wind termination shock. The observations were obtained from the plasma-wave instrument on the Voyager 2 spacecraft2. The first evidence of the approach to the shock was the detection of upstream electron plasma oscillations on 1 August 2007 at a heliocentric radial distance of 83.4 au (1 au is the Earth–Sun distance). These narrowband oscillations continued intermittently for about a month until, starting on 31 August 2007 and ending on 1 September 2007, a series of intense bursts of broadband electrostatic waves signalled a series of crossings of the termination shock at a heliocentric radial distance of 83.7 au. The spectrum of these waves is quantitatively similar to those observed at bow shocks upstream of Jupiter, Saturn, Uranus and Neptune.

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Figure 1: The first detection of electron plasma oscillations by Voyager 2 upstream of the termination shock.
Figure 2: Three bursts of broadband electrostatic noise of the type expected to occur at the termination shock.
Figure 3: A series of expanded timescale plots of the electric field intensities in the 10 to 311 Hz channels for event B.
Figure 4: Comparisons of the spectrum of the termination shock with spectra of planetary bow shocks.

References

  1. Gurnett, D. A. & Bhattacharjee, A. Introduction to Plasma Physics 277–278 (Cambridge Univ. Press, Cambridge, UK, 2005)

    Book  Google Scholar 

  2. Scarf, F. L. & Gurnett, D. A. A plasma wave investigation for the Voyager mission. Space Sci. Rev. 21, 289–308 (1977)

    Article  ADS  Google Scholar 

  3. Tonks, L. & Langmuir, I. Oscillations in ionized gases. Phys. Rev. 33, 195–210 (1929)

    Article  CAS  ADS  Google Scholar 

  4. Stix, T. H. The Theory of Plasma Waves 10 (McGraw-Hill, New York, 1962)

    MATH  Google Scholar 

  5. Gurnett, D. A. & Kurth, W. S. Electron plasma oscillations upstream of the solar wind termination shock. Science 309, 2025–2027 (2005)

    Article  CAS  ADS  Google Scholar 

  6. Stone, E. C. et al. Voyager 1 explores the termination shock region and the heliosheath. Science 309, 2017–2020 (2005)

    Article  CAS  ADS  Google Scholar 

  7. Washimi, H. et al. A forecast of the heliospheric termination-shock position by three-dimensional MHD simuluations. Astrophys. J. 670, L139–L142 (2007)

    Article  ADS  Google Scholar 

  8. Kurth, W. S., Gurnett, D. A. & Decker, R. B. in The Physics of the Inner Heliosheath: Voyager Observations, Theory, and Future Prospect (5th Annu. IGPP Internat. Astrophys. Conf.) (eds Heerikhuisen, J., Florinski, V., Zank, G. P. & Pogorelov, N. V.) 116–121 (American Institute of Physics, Melville, New York, 2006)

    Google Scholar 

  9. Burlaga, L. F. et al. Magnetic fields at the solar wind termination shock. Nature 10.1038/nature07029 (this issue)

  10. Richardson, J. D. et al. Cool heliosheath plasma and deceleration of the upstream solar wind at the termination shock. Nature 10.1038/nature07024 (this issue)

  11. Decker, R. B. et al. Mediation of the solar wind termination shock by non-thermal ions. Nature 10.1038/nature07030 (this issue)

  12. Stone, E. C. et al. An asymmetric solar wind termination shock. Nature 10.1038/nature07022 (this issue)

  13. Kurth, W. S. & Gurnett, D. A. Plasma waves as indicators of the termination shock. J. Geophys. Res. 98, 15129–15136 (1993)

    Article  ADS  Google Scholar 

  14. Gurnett, D. A. et al. First plasma wave observations at Neptune. Science 246, 1494–1498 (1989)

    Article  CAS  ADS  Google Scholar 

  15. Fredricks, R. W., Kennel, C. F., Scarf, F. L., Crook, G. M. & Green, I. M. Detection of electric-field turbulence in the Earth’s bow shock. Phys. Rev. Lett. 21, 1761–1764 (1968)

    Article  ADS  Google Scholar 

  16. Moses, S. L., Coroniti, F. V., Kennel, C. F., Kurth, W. S. & Gurnett, D. A. Comparison of plasma wave measurements in the bow shocks at Earth, Jupiter, Saturn, and Jupiter. Geophys. Res. Lett. 17, 1653–1656 (1990)

    Article  ADS  Google Scholar 

  17. Lembege, B. et al. Selected problems in collisionless-shock physics. Space Sci. Rev. 110, 161–226 (2004)

    Article  ADS  Google Scholar 

  18. Scholer, M., Shinohara, I. & Matsukiyo, S. Quasi-perpendicular shocks: Length scale of the cross-shock potential, shock reformation, and implication for shock surfing. J. Geophys. Res. 108 10.1029/2002JA009515 (2003)

  19. Filbert, P. C. & Kellogg, P. J. Electrostatic noise at the plasma frequency beyond the Earth’s bow shock. J. Geophys. Res. 84, 1369–1381 (1979)

    Article  ADS  Google Scholar 

  20. Bridge, H. S. et al. The plasma experiment on the 1977 Voyager mission. Space Sci. Rev. 21, 259–287 (1977)

    Article  ADS  Google Scholar 

  21. Krimigis, S. M. et al. The low energy charged particle (LECP) experiment on the Voyager spacecraft. Space Sci. Rev. 21, 329–354 (1977)

    Article  ADS  Google Scholar 

Download references

Acknowledgements

We wish to thank L. Burlaga and J. Richardson for discussions regarding the magnetometer and plasma data in advance of publication. The research at the University of Iowa was supported by NASA through the Jet Propulsion Laboratory.

Author Contributions D.A.G. is the principal investigator for the Voyager plasma-wave instruments and led the analysis. W.S.K. is the co-investigator and identified the wave signatures.

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Gurnett, D., Kurth, W. Intense plasma waves at and near the solar wind termination shock. Nature 454, 78–80 (2008). https://doi.org/10.1038/nature07023

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