Tests for Materials

The module compares reflectivity, transmittivity, refraction index, absorption coefficient etc. with those calculated by XOP.

Various material properties are compared with those calculated by XCrystal/XOP (also used by shadow for modeling crystal optics), XInpro/XOP and others.

Find the corresponding scripts in tests/raycing directory.

Reflectivity of mosaic crystals

These tests implement the diffraction setup from [SanchezDelRioMosaic], Fig. 4. In our case, the source has a finite energy band to demonstrate the energy dispersion effect in parafocusing (cf. Figs. 5 and 6 ibid).

The penetration depth distribution should be compared with Fig 7 ibid.

The reflectivity curves are compared with those by XCrystal/XOP [XOP]. The small differences are primarily due to small differences in the tabulations of the scattering factors. We use the one by Chantler [Chantler].

Mirror reflectivity

The small amplitude differences with XOP are due to slight differences in tabulated values of the atomic scattering factors. The phase difference between s- and p-polarized rays (calculated by xrt, cyan line, right Y axis) is not calculated by the XOP programs and therefore is given without comparison.

Slab, multilayer and coating reflectivity

Here, the phase difference between s- and p-polarized rays is given without comparison.

Note

At low energy, the result strongly depends on the used tabulation. ‘xrt-Henke’ below overplots the curves calculated by Mlayer and REFLEC that use the tabulation by Henke. ‘xrt-Chantler’ is significantly different.

Note

Mlayer/XOP does not calculate multilayers in transmission.

Transmittivity of materials

The small amplitude differences with XOP are due to slight differences in tabulated values of the atomic scattering factors.

Absorption of materials

The deviations at low energies due to differences in tabulated values of the atomic scattering factors.