Anomalous effects of radioactive decay rates and capacitance values measured inside a modified Faraday cage: Correlations with space weather

Abstract

Ra decay rate and capacitance measurements inside a modified Faraday cage. Our measurements exhibited anomalous effects of unknown origin. In this letter we report new results regarding our investigation into the origins of the observed effects. We report preliminary findings of a correlation analysis between the radioactive decay rates and capacitance time series and space weather related variables (geomagnetic field disturbances and cosmic-ray neutron counts). A significant correlation was observed for specific data sets. The results are presented and possible implications for future work discussed.Introduction. -In a recently published paper [1] we reported measurements of 226 Ra decay rates and capacitance changes inside a modified Faraday cage (MFC). The measurements exhibited anomalous effects of unknown origin. In particular, it was shown not only that the mean (or the median) values of the measurements performed outside and inside the box were different, but also that other statistics (particularly the variance) were significantly different. Regarding the anomalous variations (increase or decrease) in radiation counts, we concluded that this finding could be explained, but only partially, by changes in the electronic circuit capacitance; at the same time, these capacitance changes could not be explained. It was also shown that those anomalies were not caused by

On the recent claim of correlation between radioactive decay rates and space weather

“…Milián-Sánchez et al [27][28][29] use GM counters for their activity measurements. Given the instability and lack of selectivity of such measurement tool, it comes as no surprise that the observed decay rate of a 226 Ra source varies within a 1% range over an experiment of 100 h in December 2014.…”

“…Repeated activity measurements with the most stable instruments show absence of cyclic perturbations down to 0.023-0.00023% in amplitude [3,11], when excluding the a e-mail: stefaan.pomme@ec.europa.eu (corresponding author) susceptibility of the instrument to environmental conditions and using appropriate significance criteria [11,12]. In spite of the arguments in favour of the exponential-decay law, some authors have questioned the invariability of the decay constants [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]. Summaries of their claims and refutations by others have already been published in detail [3,[31][32][33][34].…”

“…Common denominators to the claims of violations of the exponential-decay law are the poor metrology on which they are based, the lack of an uncertainty evaluation of the attained experimental stability, and a cognitive bias towards facts contradicting the proposed conjecture. A striking example of metrological imperfection is the use of Geiger-Müller counters [19,[27][28][29], arguably among the least reliable detectors of activity and therefore unsuited to test the invariability of the decay constants. Immunisation strategies have been devised to justify the use of such instruments [29,53,54].…”

“…With most claims being convincingly refuted, there are still recent papers by Milián-Sánchez et al [27,29] and Scholkmann et al [28] to be addressed. These authors have measured background, capacitance and radioactive decay rates with a Geiger-Müller (GM) counter inside a 'modified Faraday cage' (MFC) over a short time period and assert correlations of these observables with 'space weather', in casu the 'geomagnetic activity' (GMA) and 'cosmic-ray activity' (CRA).…”

Correlations between Background Radiation Inside a Multilayer Interleaving Structure, Geomagnetic Activity, and Cosmic Radiation: A Fourth-Order Cumulant-Based Correlation Analysis

“…In subsequent works [3,4] we found correlations between some of the anomalous decay processes [1] and geomagnetic activity (GMA) as well as cosmic-ray activity (CRA). This finding is important since it showed that the measured variability in reference [1] was not caused by some failure in the electronics of the instruments but rather followed the variations in GMA and CRA.…”