Nuclear-induced UV fluorescence

An investigation of nuclear pumping of ultraviolet (UV) fluorescent gases that can be used to power the optically pumped atomic iodine laser is discussed. This laser utilizes 230-330-nm UV irradiance to dissociate compounds such as CF/sub 3/I or C/sub 3/F/sub 7/I, resulting in lasing on the 5/sup 2/P/sub 1/2/-5/sup 2/P/sub 3/2/ transition of atomic iodine at 1.31 mu m. UV fluorescence can be produced by the interaction of energetic products from nuclear reactions with a fluorescing gas. This is called a nuclear pumped flashlamp (NPF). The goal of the present phase of this work is to select an optimal gas (or gas mixture), so that the fluorescence efficiency, coupled with the overlap between the fluorescer spectral output and the photodissociation cross section of the lasant, will be maximized. Using standard gas discharge emission data, the emission spectra for select pure gases have been analyzed and compared to the photodissociation spectra of CF/sub 3/I and C/sub 3/F/sub 7/I between 230 and 330 nm. Of the potentially suitable gases, neon shows the best overlap, followed by krypton, chlorine, radon, xenon, helium, and fluorine. The best overlap is approximately a factor of 25 greater than the worst. Excimer mixtures, which can have very high emission efficiencies around a particular wavelength, are also being investigated as likely candidates.<>