Testing claims of the GW170817 binary neutron star inspiral affecting ${\hat{I}}^2$-decay rates

Abstract

On August 17, 2017, the first gravitational wave signal from a binary neutron star inspiral (GW170817) was detected by Advanced LIGO and Advanced VIRGO. Here we present radioactive ${\hat{I}}^2$-decay rates of three independent sources ${}^{44}$Ti, ${}^{60}$Co and ${}^{137}$Cs, monitored during the same period by a precision experiment designed to investigate the decay of long-lived radioactive sources. We do not find any significant correlations between decay rates in a 5\,h time interval following the GW170817 observation. This contradicts a previous claim published in this journal of an observed 2.5$\ddot{I}ƒ$ Pearson Correlation between fluctuations in the number of observed decays from two ${\hat{I}}^2$-decaying isotopes (${}^{32}$Si and ${}^{36}$Cl) in the same time interval. By correcting for the choice of an arbitrary time interval, we find no evidence of a correlation above 1.5$\ddot{I}ƒ$ confidence. In addition, we argue that such analyses on correlations in arbitrary time intervals should always correct for the so-called Look-Elsewhere effect by quoting the global significance.

6 pages, 1 figure