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Particle-gamma coincidences from the 46Ti(p,p gamma)46Ti inelastic scattering reaction with 15-MeV protons are utilized to obtain gamma-ray spectra as a function of excitation energy. The rich data set allows analyzing the coincidence data with various gates on excitation energy. This enables, for many independent data sets, a simultaneous extraction of level density and radiative strength function (RSF). The results are consistent with one common level density. The data seem to exhibit a universal RSF as the deduced RSFs from different excitation energies show only small fluctuations provided that only excitation energies above 3 MeV are taken into account. If transitions to well-separated low-energy levels are included, the deduced RSF may change by a factor of 2-3, which might be expected due to the involved Porter-Thomas fluctuations.
A study is made of the behavior of unstable states in simple models which nevertheless are realistic representations of situations occurring in nature. It is demonstrated that a non-exponential decay pattern will ultimately dominate decay due to a lo
Fermis golden rule underpins the investigation of mobile carriers propagating through various solids, being a standard tool to calculate their scattering rates. As such, it provides a perturbative estimate under the implicit assumption that the effec
We discuss the decay of unstable states into a quasicontinuum using models of the effective Hamiltonian type. The goal is to show that exponential decay and the golden rule are exact in a suitable scaling limit, and that there is an associated renorm
Fermis golden rule defines the transition rate between weakly coupled states and can thus be used to describe a multitude of molecular processes including electron-transfer reactions and light-matter interaction. However, it can only be calculated if
We study heating dynamics in isolated quantum many-body systems driven periodically at high frequency and large amplitude. Combining the high-frequency expansion for the Floquet Hamiltonian with Fermis golden rule (FGR), we develop a master equation