The spectrum of small-scale density fluctuations in the solar wind
Interplanetary scintillation observations at frequencies between 74 and 1400 MHz and solar elongations in the range 10–90° are combined to determine the form of the wavenumber spectrum of electron density fluctuations in the range 10⁻³ < k < 10⁻¹/km (where k = 2π/λ). The data are best explained by a spectrum in which there is a genuine scale-length; they are not consistent with a simple power-law spectrum. This suggests that turbulence may be less important than some kind of plasma instability in generating small-scale density fluctuations. The relevance of these conclusions to the use of IPS for determining radio source structure is discussed.
Additional Information© 1978 Royal Astronomical Society. Provided by the NASA Astrophysics Data System. Received 1978 March 20; in original form 1977 November 9. We thank G. Bourgois, A. G. F. Brown and L. T. Little for providing data prior to publication, and the referee for helpful comments. ACSR is indebted to the Royal Society for a fellowship supported by the Weir Foundation, MCK gratefully acknowledges the support of an SRC studentship.
Published - mnras185-0207.pdf