(a) Side view of ray tracing for a single analyzer crystal. (b) Front view: Ray tracing from real source to analyzer crystals has been left off for clarity. Note that only ∼30% of each analyzer crystal is active.
A 3D cutaway rendering of the spectrometer.
A rendering of the full spectrometer assembly. The side view is looking downstream along the beam.
A photograph of the Fe Kβ spectrometer, viewed from the opposite perspective as Fig. 2.
(a) A composite image formed from 15 exposures taken at evenly spaced incident beam energies across the range of the spectrometer. (b) The calibrated 2D-PSD face.
A 300-s exposure of Fe3O4 Kβ fluorescence at 7800-eV incident energy. Emission energy runs vertically downward. A nonlinear color scale was chosen to highlight the labeled spectral features. The incident flux was ∼1012 photons/s.
Kβ emission spectra for (a) Fe3O4 (corresponding to raw data in Fig. 6) and (b) FeS. The incident beam was at 7.8 keV, with an incident flux ∼1012 photons/s. The integration time was 300 s and 500 s, respectively. Note that the scale for FeS is an order of magnitude smaller than for Fe3O4 due to the sample being substantially thinner than an absorption length. The scale on the left side shows counts/sr/s. The scale on the right is normalized to counts/eV/s. The total integrated counts rates are 18 800 and 2500 counts/s, respectively.
Selected Bragg angles for 3d transition metal Kβ lines. E 1, 3 and E 2, 5 give energies of Kβ1, 3 and Kβ2, 5 lines in eV.56 The corresponding Bragg angles are given by θ(E). If only the main Kβ peak is of interest, then the required angular range is from θ(E 1, 3 + 20) to θ(E 1, 3 − 45). To include the valence emission, the lower Bragg angle should be extended to θ(E 2, 5 + 20).
Results of a photometric analysis for the present spectrometer (miniXES) and a commercial Si drift detector (SDD). The ratio of the measured count rates (Γ) is compared to the ratio of the theoretical detector efficiencies (η).
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