X-ray energy dispersive spectroscopy of uranium ore using a TES microcalorimeter mounted on a field-emission scanning electron microscope

Energy dispersive spectroscopic measurements of uranium ore were conducted using a superconducting phase transition-edge-thermosensor (TES) microcalorimeter mounted on a field-emission scanning electron microscope (SEM) to demonstrate its potential for high-precision microanalysis. The effective solid angle for X-ray detection is found to be larger than 2 msr by precise adjustments in the X-ray polycapillary alignment. The observed detection signal pulses with decay time constant of 50μs enable maximum count rates larger than 300 counts per second. The energy resolution was determined to be 14.6 eV FWHM at Al Kα X-ray energies of 1487 eV. Distinct peaks appear in the resulting X-ra y energy spectrum associated with U-Mα, U-Mβ and U-Mγ X-rays emitted by the uranium ore specimens. This spectrum includes weaker peaks corresponding to C-Kα, Fe-Lα, Cu-L and Sr L α1 X rays.