Generalized Lomb–Scargle analysis of $${^{123}\mathrm{I}}$$ and $${^{99\mathrm{m}}\mathrm{Tc}}$$ decay rate measurements

Abstract

We apply the generalized Lomb–Scargle periodogram to the $${^{123}\text {I}}$$ 123 I and $${^{99\mathrm{m}}\text {Tc}}$$ 99 m Tc decay rate measurements based on data taken at the Bronson Methodist Hospital. The aim of this exercise was to carry out an independent search for sinusoidal modulation for these radionuclei (to complement the analysis in Borrello et al.) at frequencies for which other radionuclei have shown periodicities. We do not find such a modulation at any frequencies, including annual modulation or at frequencies associated with solar rotation. Our analysis codes and datasets have been made publicly available.

Generalized Lomb–Scargle analysis of 22 years of super-Kamiokande solar $$^8$$B neutrino data

“…Since we did not find any peaks with large statistical significance above a frequency of 20/year, we do not show any results for the same. We followed the same normalization convention for the L-S periodogram as in our previous works [19][20][21], where the L-S power can take values between zero and one. In the appendix, we also show the results of the same analyses using only the first five years of Super-K data until July 2001.…”

“…In this work, we again apply the generalized Lomb-Scargle periodogram (as our previous work [10]) to the aforementioned Super-K data [17]. We evaluate the statistical significance using four independent methods, similar to our recent works on searching for periodicities in nuclear β-decay rates [19][20][21]. This manuscript is structured as follows.…”