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arXiv · 1801.03236

Generalized Lomb-Scargle analysis of $\rm{^{90}Sr/^{90}Y}$ decay rate measurements from the Physikalisch-Technische Bundesanstalt

P Tejas·Shantanu Desai
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Abstract

We apply the generalized Lomb-Scargle (LS) periodogram to independently confirm the claim by Sturrock et al (arXiv:1605.03088) of oscillation at a frequency of 11/year in the decay rates of $\rm{^{90}Sr/^{90}Y}$ from measurements at the Physikalisch Technische Bundesanstalt (PTB), which however has been disputed by Kossert and Nahle (arXiv:1407.2493). For this analysis, we made two different {\it ansatze} for the errors. For each peak in the LS periodogram, we evaluate the statistical significance using non-parametric bootstrap resampling. We find using both of these error models evidence for ~11/year periodicity in the $\rm{^{90}Sr/^{90}Y}$ data for two of the three samples, but at a lower significance than that claimed by Sturrock et al.

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P Tejas, Shantanu Desai. 2018-07-02. Generalized Lomb-Scargle analysis of $\rm{^{90}Sr/^{90}Y}$ decay rate measurements from the Physikalisch-Technische Bundesanstalt. https://doi.org/10.1140/epjc%2Fs10052-018-6040-5

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