Figure 1
(a) A three-dimensional illustration of GTSAXS and GISAXS geometries. The incident beam (red arrow) impinges on the sample at a grazing angle of [\alpha_{\rm i}] and the scattered beam is collected by an area detector. The direct incoming beam (orange dotted line) goes through the origin of the qr-qz reciprocal space. In the scattering image, the solid line [[q_z = (2\pi/\lambda) \sin \alpha_{\rm i}]] marks the surface horizon, which divides the whole scattering image into the GTSAXS and GISAXS regimes. The dotted line corresponds to the direct beam (qz = 0). (b) A two-dimensional Ewald sphere illustration of the GTSAXS, GISAXS and TSAXS regimes. The rather large grazing incident angle shown is for illustrative purpose. In GISAXS measurements [\alpha_{\rm i}] is close to grazing incidence and in TSAXS the range is typically [20 \leq \alpha_{\rm i} \leq 90]°.  [article HTML]

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