\(\Gamma = \frac{\hbar}{\tau}\), where \(\hbar\) is the reduced Planck constant and \(\tau\) is the mean lifetime.
n4:latexSymbol
\(\Gamma\)
n4:plainTextDescription
The "Level Width" is the uncertainty in the energy of a quantum-mechanical system having discrete energy levels in a state that is not strictly stationary. The system may be an atom, a molecule, or an atomic nucleus.