  This paper presents a new analysis of the observations of radon decay in an
enclosed environment by the Geological Survey of Israel (GSI) between 2007 and
2012 [4]; for a more complete list of experiments performed by GSI on radon see
also references [1-3]. The data exhibit a large peak around local noon followed
by an abrupt drop, and by a second peak around 6PM local time. Additionally,
there is also a very low amplitude peak occurring before daybreak. The salient
features of the GSI radon decay data can be modeled as arising from a change in
the radon decay rate, rather than due to the changes in the local concentration
of radon (N0). Such a model may provide a clue to long theorized axionic, dark
matter, interactions. Finally, new experimentation is suggested that can
distinguish between changes in N0 versus changes in decay rate. Should a
follow-up experiment show an effect similar to that seen in GSI, this could
have significant implications for elementary particle physics.
