Integral diffraction coefficients of the crystal are the essential data of a crystal spectrometer which is extensively used to measure quantitative x-ray spectra of high temperature plasmas in kilo-electron-volt region. An experimental method has been developed to measure the integral diffraction coefficients of crystals on beamline 4B7 of Beijing Synchrotron Radiation Facility. The integral diffraction coefficients of several crystals including polyethylene terephthalate (PET), thallium acid phthalate (T1AP) and rubidium acid phthalate (RAP) crystals have been measured in the x-ray energy range 2100-5600 eV and compared with the calculations of the 'Darwin Prins' and the 'Mosaic' models. It is shown that the integral diffraction coefficients of these crystals are between the calculations of the 'Darwin Prins' and the 'Mosaic' models, but more close to the 'Darwin Prins' model calculations.
The 4s4p excitation energies and the 4s24s4pE1 transitions for zinc-like ions from Z = 48 to 54 are calculated by the multi-configuration Dirac-Hartree-Fock (MCDHF) method in this paper. The results for fine-structure energy levels, wavelengths and lifetimes between Z = 48 (Cd) and Z = 54 (Xe) are presented and compared with other theoretical and experimental results. The calculated values including core-valence correlation are found to be very similar to other theoretical and experimental values. We believe that our calculated values can guide experimentalists in identifying the fine-structure levels in their future work.
A spectroscopic diagnostic method, to measure electron temperature of radiationheated CH foam on Shenguang Ⅱ laser facility, is described. A tracer layer of aluminum was embedded in the middle of the CH foam and a point-projection method used in the opacity experiment was induced to measure the transmission spectrum of the embedded Al foil. The electron temperature, of about 80 eV, was deduced through a comparison of the experimental absorption spectrum with the calculated one with a detailed level accounting opacity code. The results of hydrodynamic simulation show that it's reasonable to determine the CH foam temperature by measuring the embedded Al absorption spectrum. Thus, the electron temperature of radiationheated CH foam was obtained.