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A Search for Fine Structure of the Knee in EAS Size Spectra

G. Schatz
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Abstract

28 size spectra of extensive air showers from 7 different experiments are analysed consistently. They are fitted by adjusting either 4 or 5 parameters: knee position, power law exponents above and below the knee, overall intensity and, in addition, a parameter describing the smoothness of the bend. The residuals are then normalized to the same knee position and averaged. When 5 parameters are employed no systematic deviation from a single smooth knee is apparent at the 1% level up to a factor of 4 above the knee. At larger shower sizes a moderately significant deviation can be seen whose shape and position are compatible with a second knee caused by iron group nuclei.

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G. Schatz. 2001-04-17. A Search for Fine Structure of the Knee in EAS Size Spectra. https://doi.org/10.1016/s0927-6505(01)00130-x

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