X-ray fluorescence measurements of 412 inorganic compounds

In a search for new, fast, inorganic scintillators, 412 inorganic compounds have been exposed to 0.5-ns pulses of 20-keV X-rays and their fluorescent emissions have been measured. Most of these compounds were dense (>4 g/cm/sup 3/), contained heavy cations such as Pb, Bi, Ba, or a rare-earth element, and anions such as O, F, Cl, Br, I, CO/sub 3/, SO/sub 4/ and PO/sub 4/. About half were undoped compounds and half contained 0.1% to 10% rare-earth dopants. Standard scintillators such as BaF/sub 2/ and BGO were included for reference. The authors report total luminosities and fitted exponential decay times and percentages for 97 compounds having either a luminosity >40% of BGO, or an initial photon intensity greater than BGO, or a component decay time <1 ns. Emission wavelengths are listed for 53 of these compounds. Significant fast emissions were seen from Y/sub 2/SiO/sub 5/:Ce, CeCl/sub 3/, BaCl/sub 2/, PbSO/sub 4/, and LuPO/sub 4/:Ce. Other less luminous compounds, i.e., Yb/sub 2/O/sub 3/, CuI, CuBr, and BiPO/sub 4/:Gd, exhibited components with shorter decay times than ZnO:Ga and BaF/sub 2/.<>