THERMAL-ANALYSIS IN THE LASER-HEATED DIAMOND-ANVIL CELL

A new technique actively controls thermal radiation and monitors sampl e properties during laser-heating in a diamond anvil cell. The techniq ue can be described as a qualitative application of thermal analysis. Discontinuities in temperature. laser power, visible thermal radiation , or in their derivatives as functions of time can be associated with the enthalpy of phase transitions (such as melting) or with changes in material properties (such as emissivity). The technique is illustrate d with melting experiments on iron-magnesium-silicate perovskite. Temp erature corrections associated with these experiments are discussed an d the results are briefly reviewed.