In the method being developed, a near-ultraviolet laser is used to saturate a fingerprintlike
optical absorption band of Cm3+ in aqueous solution and thereby optimize the probability
that the Cm3+ ions in the sample will fluoresce following each laser pulse. Population of a
lower-lying metastable excited electronic state of Cm3+ occurs via nonradiative decay. The
orange light emitted by the metastable state is collected, spectrally filtered with high efficiency,
and detected using a cooled photodetector. Additional enhancement of fluorescence will be
achieved by solvent deuteration. Combining optical saturation with time- and wavelength
resolution of fluorescence emission from Cm3+ will result in very high sensitivity and excellent
assurance that the species being detected is Cm3+. Because only trivalent curium is stable in