BL39XU X-ray emission spectrometer
問い合わせ番号
INS-0000001619
X-ray emission spectrometer
The spectrometer for X-ray emission spectroscopy (XES) is equipped at BL39XU.
XES is a method to monochromatize fluorescent X-rays emitted from a sample with high-energy resolution (< 1 eV) by using analyzer crystals.
High-energy resolution fluorescence detection X-ray abosorption spectrum (HERFD-XAS), which is obtained by scanning incident photon energy under the fixed emission energy (at the fluorescence peak), has a high-energy resolution compared with the conventional-XAS so that the method can be observed fine structures and their tiny variation of the spectra.
The intensity of XES due to the secondary optical process is very weak. To shore up the weak point, multi-analyzer crystals with 15 crystals in maximum are available for the XES spectrometer (see in Figure 1 and Table 1).
Energy range for each reflection plane is limited because of using Bragg reflection, but BL39XU has many crystals with different reflection plane, which covers a wide energy range for the emission (see in Figure 2).
Currently, Ge 111 and Ge 220 crystals of 15 analyzer crystals are available for high-efficiency measurements, but other crystals with various reflection plane will be planned to prepare in sequence.
- Table 1. Specifications of the X-ray emission spectrometer.
Method Rowland mount type Rowland radius 820 mm Available energy range for emission 4.42-18 keV Detector PILATUS 100K (Si) / PiXirad-2 (CdTe) / SOPHIAS-L (Si) Available analyzer crystals See in figure 2 Sample environment at room temperature XYZ translation - θχ rotation Sample environment at low temperature He-flowing type cryostat (11-330 K) / Pulse-tube type cryostat (3-300 K) (XZ translation) Sample environment at high pressure A.P.-100 GPa (room temperature), A.P.-40 GPa (low temperature) Sample space ~φ100 mm
Figure 1. X-ray emission spectrometer.
Figure 2. Available analyzer crystals. Number in ( ) denotes number of analyzer crystals. Contrastly, unavailable energy range is denoted in a region displayed purple color.