Non-Exponential Decay of Nuclei -A Search for a Fundamental Quantum Effect in Nuclei

摘要

Modern tests of grand unification theories have spent considerable experimental effort in pursuit of rare decays. A common feature of these experiments is that they involve extremely rare decay processes and probe regions of the systems' decay curves which are very short in time compared to their expected mean lifetimes, A potential complication to interpretation of such experiments is the approximate nature of the exponential decay law for quasi-stationary states. Using the decay of the isomeric nuclear state ~(207m)Pb in the short time limit, we search for predicted deviations from the exponential decay law. These experiments address the short-time electromagnetic decays of nuclei with half-lives on the order of a few seconds, and explore the as-yet untapped electromagnetic sector for short-time (t_(min)/t_(1/2))≈10~(-5)) violations of the exponential decay law. Isomeric states are photo-populated via (γ, n) reactions with bremsstrahlung beams.