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On the reliability of peak-flux distributions, with an application to solar flares

H. Isliker·A. O. Benz
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Abstract

Narrow-band radio spikes have been recorded during a solar flare with unprecedented resolution. This unique example allows to study the effect of low resolution in previously published peak-flux distributions of radio spikes. We give a general, analytical expression for how an actual peak-flux distribution is changed in shape if the peaks are determined with low temporal and/or frequency resolution. It turns out that, generally, low resolution tends to cause an exponential behavior at large flux values if the actual distribution is of power-law shape. The distribution may be severely altered if the burst-duration depends on the peak-flux. The derived expression is applicable also to peak-flux distributions derived at other wavelengths (e.g. soft and hard X-rays, EUV). We show that for the analyzed spike-event the resolution was sufficient for a reliable peak flux distribution. It can be fitted by generalized power-laws or by an exponential.

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H. Isliker, A. O. Benz. 2001-08-23. On the reliability of peak-flux distributions, with an application to solar flares. https://doi.org/10.1051/0004-6361%3A20010899

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