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arXiv · 1207.2482

Ultra-High Resolution Intensity Statistics of a Scintillating Source

Michael D. Johnson·Carl R. Gwinn
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Abstract

We derive the distribution of flux density of a compact source exhibiting strong diffractive scintillation. Our treatment accounts for arbitrary spectral averaging, spatially-extended source emission, and the possibility of intrinsic variability within the averaging time, as is typical for pulsars. We also derive the modulation index and present a technique for estimating the self-noise of the distribution, which can be used to identify amplitude variations on timescales shorter than the spectral accumulation time. Our results enable a for direct comparison with ultra-high resolution observations of pulsars, particularly single-pulse studies with Nyquist-limited resolution, and can be used to identify the spatial emission structure of individual pulses at a small fraction of the diffractive scale.

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Michael D. Johnson, Carl R. Gwinn. 2012-07-10. Ultra-High Resolution Intensity Statistics of a Scintillating Source. https://doi.org/10.1088/0004-637x%2F755%2F2%2F179

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