Horne R. B., R. M. Thorne, S. A. Glauert, J. Douglas Menietti, Y. Y. Shprits, D. A. Gurnett, (2008), Gyro-resonant electron acceleration at Jupiter, Nature Physics, 4, 301-304, doi:10.1038/nphys897

Abstract

According to existing theory, electrons are accelerated up to ultra-relativistic energies1 inside Jupiter’s magnetic field by betatron and Fermi processes as a result of radial diffusion towards the planet and conservation of the first two adiabatic invariants2,3,4. Recently, it has been shown that gyro-resonant electron acceleration by whistler-mode waves5,6 is a major, if not dominant7, process for accelerating electrons inside the Earth’s outer radiation zone, and has redefined our concept for producing the Van Allen radiation belts8. Here, we present a survey of data from the Galileo spacecraft at Jupiter, which shows that intense whistler-mode waves are observed outside the orbit of the moon Io and, using Fokker–Planck simulations, are strong enough to accelerate electrons to relativistic energies on timescales comparable to that for electron transport. Gyro-resonant acceleration is most effective between 6 and 12 jovian radii (Rj) and provides the missing step in the production of intense synchrotron radiation from Jupiter

Authors (sorted by name)

Douglas Menietti Glauert Gurnett Horne Shprits Thorne

Journal / Conference

Nature Physics

Acknowledgments

We thank H. B. Garrett and B. Mauk for providing electron data, F. Bagenal for her plasma density model and J. Oliver for producing Fig. 5. This work was supported by the UK NERC, NSF grants ATM-0402615 and ATM-0603191 and NASA grant NNM06AA75C.

Grants

ATM-0402615 ATM‐0603191 NNM06AA75C

Bibtex

@article{nature10.1038/nphys897.,
author = {Horne, Richard B. and Thorne, Richard M. and Glauert, Sarah A. and Douglas Menietti, J. and Shprits, Yuri Y. and Gurnett, Donald A.},
title = {Gyro-resonant electron acceleration at Jupiter},
journal = {Nature Physics},
year = {2008},
volume = {4},
number = {},
pages = {301-304},
doi = {10.1038/nphys897},
abstract = {According to existing theory, electrons are accelerated up to ultra-relativistic energies1 inside Jupiter’s magnetic field by betatron and Fermi processes as a result of radial diffusion towards the planet and conservation of the first two adiabatic invariants2,3,4. Recently, it has been shown that gyro-resonant electron acceleration by whistler-mode waves5,6 is a major, if not dominant7, process for accelerating electrons inside the Earth’s outer radiation zone, and has redefined our concept for producing the Van Allen radiation belts8. Here, we present a survey of data from the Galileo spacecraft at Jupiter, which shows that intense whistler-mode waves are observed outside the orbit of the moon Io and, using Fokker–Planck simulations, are strong enough to accelerate electrons to relativistic energies on timescales comparable to that for electron transport. Gyro-resonant acceleration is most effective between 6 and 12 jovian radii (Rj) and provides the missing step in the production of intense synchrotron radiation from Jupiter}
}