AXIAL TEMPERATURE-GRADIENTS IN DIELECTRIC SAMPLES IN THE LASER-HEATEDDIAMOND CELL

Temperature gradients inside the laser-heated diamond cell are not mea sured in the axial direction, along the optic axis, yet can bias estim ates of the peak temperatures achieved in optically thin (dielectric) samples such as Mg-silicate perovskite. Thermal diffusion calculations show that the observed thermal-radiation spectrum is not significantl y affected by axial temperature gradients. The apparent (measured) tem perature underestimates the actual peak sample temperature by 350-850 K for 4000 < T < 6000 K.