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The local Poisson hypothesis for solar flares

M. S. Wheatland
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Abstract

The question of whether flares occur as a Poisson process has important consequences for flare physics. Recently Lepreti et al. presented evidence for local departure from Poisson statistics in the Geostationary Operational Environmental Satellite (GOES) X-ray flare catalog. Here it is argued that this effect arises from a selection effect inherent in the soft X-ray observations; namely that the slow decay of enhanced flux following a large flare makes detection of subsequent flares less likely. It is also shown that the power-law tail of the GOES waiting-time distribution varies with the solar cycle. This counts against any intrinsic significance to the appearance of a power law, or to the value of its index.

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M. S. Wheatland. 2001-07-09. The local Poisson hypothesis for solar flares. https://arxiv.org/abs/astro-ph/0107147

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