دورية
Dynamic spectra of interplanetary scintillations
| العنوان: | Dynamic spectra of interplanetary scintillations |
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| المؤلفون: | Coles, W. A., Filice, J. P. |
| المصدر: | Nature; November 1984, Vol. 312 Issue: 5991 p251-254, 4p |
| مستخلص: | Interplanetary scintillations (IPS) are fluctuations in the apparent intensity of radio sources caused by fluctuations in the electron density of the solar wind1. Observations at a single wavelength provide information on the spatial spectrum of electron density at scales of the order of the radius of the first Fresnel zone. However, dynamic spectra covering a wide range of wavelengths show evidence of fluctuations on a much larger scale2. Unfortunately, the problem of estimation of the spatial spectrum at this larger scale is analytically intractable. Here we compare the observations2with a numerical simulation of the diffraction of plane waves by a two-dimensional random phase screen. The frequency–time structure of the simulated IPS shows good qualitative agreement with the observations when the turbulence spectrum in the phase screen is a simple power law with the Kolmogorov exponent. No ad hoc large-scale structure is necessary to account for the observations. |
| قاعدة البيانات: | Supplemental Index |
| تدمد: | 00280836 14764687 |
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| DOI: | 10.1038/312251a0 |