000003089 001__ 3089
000003089 005__ 20170116144206.0
000003089 037__ $$aCTALK-2017-0034
000003089 100__ $$aRyan, Daniel
000003089 245__ $$aThe Effects of Flare Definitions on the Statistics of Derived Flare Distributions
000003089 260__ $$c2016
000003089 269__ $$c2016-05-31
000003089 520__ $$aThe statistical examination of solar flares is crucial to revealing their global characteristics and behaviour. However, statistical flare studies are often performed using standard but basic flare detection algorithms relying on arbitrary thresholds which may affect the derived flare distributions. We explore the effect of the arbitrary thresholds used in the GOES event list and LYRA Flare Finder algorithms. We find that there is a small but significant relationship between the power law exponent of the GOES flare peak flux frequency distribution and the algorithms’ flare start thresholds. We also find that the power law exponents of these distributions are not stable but appear to steepen with increasing peak flux. This implies that the observed flare size distribution may not be a power law at all. We show that depending on the true value of the exponent of the flare size distribution, this deviation from a power law may be due to flares missed by the flare detection algorithms. However, it is not possible determine the true exponent from GOES/XRS observations. Additionally we find that the PROBA2/LYRA flare size distributions are clearly non-power law. We show that this is consistent with an insufficient degradation correction which causes LYRA absolute irradiance values to be unreliable. This means that they should not be used for flare statistics or energetics unless degradation is adequately accounted for. However they can be used to study time variations over shorter timescales and for space weather monitoring. 
000003089 594__ $$aNO
000003089 700__ $$aDominique, Marie
000003089 700__ $$aSeaton, Daniel B.
000003089 700__ $$aStegen, Koen
000003089 700__ $$aWhite, Arthur
000003089 773__ $$tSPD meeting
000003089 8560_ $$fmarie.dominique@observatoire.be
000003089 906__ $$aContributed
000003089 980__ $$aCTALKCONT