This talk will highlight a unique scientific collaboration searching for anomalous nuclear decays by exploiting daily "check source" measurements across the International Monitoring System (IMS).  The IMS, a worldwide network of radionuclide monitoring stations that help to verify compliance with the Comprehensive Nuclear Test-Ban Treaty, features long duration monitoring of radionuclides and permits an unprecedented opportunity to evaluate long-term systematic effects on HPGe detector stability.  An understanding of these effects is often crucial to physics experiments designed to evaluate exotic or anomalous nuclear decays over many years.
            The investigation documented a number of systematic effects across many IMS detectors as well as a number of statistically significant and unexplained periodicities occurring among the measured "check source" photo-peaks. The implications of these unexplained periodicities are examined in the context of searches for new physical phenomena and related to results of other recent experiments reporting anomalous decays.   
            In addition, the talk will also seek to highlight the applicability of techniques from High Energy Physics and Bayesian analytic methods in the review of standard nuclear detector diagnostics and time-series interpretation of radionuclide data.