Population inversion field, to use quantum coherence effects to reduce the likelihood of an excited-state to ground-state transition. This technique, known as lasing without inversion, allows optical amplification to take place without producing a population inversion between the two states. Stimulated emission was first observed in the microwave region of the electromagnetic spectrum, giving rise to the acronym MASER for Microwave Amplification by Stimulated Emission of Radiation. In the microwave region, the Boltzmann distribution of molecules among energy states is such that, at room temperature all states are populated almost equally. To create a population inversion under these conditions, it is necessary
Neutron stimulated emission computed tomography Neutron stimulated emission computed tomography Neutron stimulated emission computed tomography (NSECT) uses induced gamma emission through neutron inelastic scattering to generate images of the spatial distribution of elements in a sample. NSECT has been shown to be effective in detecting liver iron overload disorders and breast cancer. Due to its sensitivity in measuring elemental concentrations, NSECT is currently being developed for cancer staging, among other medical applications. A given atomic nucleus, defined by its proton and neutron numbers, is a quantized system with a set of characteristic higher energy levels that it can occupy as a nuclear isomer. When the