(a) Visible transmission microscope images of a duo-lateral transmissive PSD-XBPM with active area (Serial No. 2513-15B). Left: detector and holder; right: zoom of active area. (b) Corresponding wiring scheme.
(a) Visible bright field microscope image of the tetra-lateral transmissive PSD-XBPM with active area (Serial No. 2513-16A). Left: detector and holder, right: zoom of active area. (b) Corresponding wiring scheme.
(a) Cross section of a duo-lateral transmissive PSD. Electrodes drawn parallel (as opposed to orthogonal) for clarity. Not drawn to scale. (b) computer-aided design (CAD) rendering of a PSD mounted on its alumina ceramic detector support. The front side is the anode, the rear side is the cathode side of the duo-lateral detector.
Measured anode current sum signal from a duo-lateral PSD compared to predicted currents from measured flux values, tabulated absorption coefficients, and mean energy for creation of an electron-hole pair in Si.
Measured transmission curves of two duo-lateral PSDs (Serial Nos. 2513-1D and 2513-15B) for the combined KMC-1 and BL14.1 beamline photon energy range. Calculated x-ray transmission curves16 of thick Si foils are plotted for comparison.
Expected signals from an ideal PSD of length in one dimension and a beam size of (FWHM) according to the convolution model described following Eq. (7). describes the position response, the intrinsic detector sensitivity function, the beam intensity distribution, and the detector sensitivity function for a PSD, and and the associated electrode currents.
(a) Anode currents and and cathode currents and of the duo-lateral PSD (Serial No. 2513-1D) plotted against the beam position for a horizontal sweep of the beam at . (b) Difference-over-sum signal vs horizontal translation stage position with linear fit to the central linear range (open circles) and residual. The linearity range of was limited by convolution of the detector response function with the finite beam size of (Fig. 6).
(a) Anode photocurrents and (b) difference-over-sum signal from the duo-lateral detector (Serial No. 2513-15A). The measurement was done behind a capillary optics at , beam size, and following a vertical scan with step size at bandwidth.
Photo current maps (A and B) and sum signal as well as the difference/sum from the duo-lateral detector behind a capillary at and beam size taken with step width at bandwidth. All maps normalized to range [0 1], see color table.
Measured pincushion effect for the tetra-lateral detector (Serial No. 2513-16). Horizontal cross-talk signals during vertical sweeps and vertical cross-talk signals during horizontal sweeps of the beam across the detector area [see Eq. 2]. The sweep traces separation was adjusted manually to .
Signal-to-noise ratio (S/N) comparison of a duo-lateral (DL, Serial No. 2513-15B) and a tetra-lateral detector (TL, Serial No. 2513-16) for different bandwidths. Up to a detection bandwidth of , the S/N exceeds a factor of , corresponding to submicron resolution.
Translation stage steps of a tetra-lateral detector at bandwidths of and . Both steps cover a width of .
Detection of selectively excited vibrations. The normalized amplitude of the excitation frequency as detected via the cathode and anode currents of a duo-lateral detector is plotted vs the excitation frequency. The level is indicated with a dashed line.
Position response of the (Serial No. 2513-1D) duo-lateral PSD with closed and open PID-feedback loop, respectively, at the KMC-1 monochromator. Damping of residual noise is mainly limited by the frequency response of the actuator.
Time traces of the position signal from a tetra-lateral detector (Serial No. 2513-16) after exciting a seismic oscillation. A clear detection of peak amplitudes at bandwidth is possible.
PSD detectors under test in the present publication. For the duo-lateral detectors, the interelectrode resistances are given for anode and cathode, for the tetra-lateral device (Serial No. 2513-16), just of the anode side is stated since the counter cathode covers the complete back side. The leakage current was measured with an applied bias voltage of .
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