The laser-induced fluorescence lifetime of 30 nm particles of YAG:Ce was measured as a function of temperature from 7 to 77°C. The fluorescence decay lifetimes for the nanoparticles of this phosphor varied from ≈18 to 27 ns, i.e. ≈33% relative to the longest lifetime measured. This large variation in lifetime, coupled with the high signal strength that was observed, suggest that YAG:Ce nanoparticles will be useful thermographic phosphors. We describe the material and the apparatus used to characterize its fluorescence, present the results of measurements made over the range of temperatures tested and comment on some possible applications for this novel material.

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Fluorescence from three samples of YAG:Tm, and three samples of YAG:Dy, with different activator concentrations, was measured for a wide temperature range, extending from room temperature to about 1700 C. Fluorescence lifetimes were measured for emissions at 460 nm from the YAG:Tm and at 453, 480, and 575 nm from YAG:Dy. The measurement system is described, including techniques for accommodating the high background blackbody radiation encountered at these very high temperatures. Data compilations are shown, including the fluorescence lifetimes over the temperature range of the measurement. This study has extended the high-temperature range of phosphor thermometry by approximately 200 C and shown the feasibility of using phosphor materials for very high temperature noncontact thermometry, opening up further applications for engines, materials, high-temperature processing, and related areas.

We report initial results of exposing low-Z solid and high-Z liquid targets to 150-ns, 4 × 10 12 proton pulses with spot sizes on the order of 1 to 2 mm. The energy deposition density approached 100 J/g. Diagnostics included fiberoptic strain sensors on the solid target and high-speed photography of the liquid targets. This work is part of the R&D program of the Neutrino Factory and Muon Collider Collaboration.

The temperature dependence of the lifetimes of two phosphors, La2O2S:Eu and Mg4FGeO6:Mn, is presented from 300 to 11 and 140 to 8 K, respectively. Emission from the D35 state of La2O2S:Eu reveals a strong temperature dependence from 11 to about 130 K, where the signal becomes too weak to measure accurately. Emission from the F24 state of Mg4FGeO6:Mn changes throughout the temperature range measured. Both of these materials are used for higher temperature thermometry applications. This work illustrates their utility down to liquid helium temperatures.