Presentation materials
Imperfection in X-ray focusing optical elements result in phase errors which when propagated to the focal plane cause broadening of the focused beam profile. A useful concept is the X-ray wavefront which is a surface of constant phase and for ideal focusing this is a spherical surface centred on the focal point. Aberrations in optical elements cause a deviation of the wavefront from this ideal...
Blazed gratings are an essential element for instruments used at free electron laser and synchrotron facilities in soft and tender X-ray ranges. Their application ranges from beamline monochromators and spectrometer analyzers to self-seeding and pulse compression elements. These gratings are commonly made by mechanical ruling, however, the production time of high-quality blazed gratings has...
The XRD2 and XPRESS beamlines of Elettra, the Italian synchrotron facility, share a multipole semiconducting wiggler as photon source. XRD2 receives light from the central portion of the photon beam while a Si(111) beam splitter, at an incident angle of 4.5°, reflects a side portion of the radiation cone towards XPRESS. Upon dismounting, the crystal showed an unexpected, longitudinal, 4...
We present the Diamond-VeNOM (velocity-NOM): a high-speed slope profiler of X-ray optics. With recent improvements in the fabrication quality of X-ray mirrors, the systematic errors of optical profilers are no longer negligible. For optics with slope errors << 100 nrad rms, repeated scans with the mirror oriented in a range of configurations are required to null experimental errors and improve...
In the past 5 years, the LCLS Optics Metrology Laboratory has measured and encountered numerous types of extreme x-ray optics in various phases, i.e. from prototyping to qualifying the bare optics to the fully assembled optics systems. In this presentation, selected examples of optic work will be shared for illustrating the interesting experience working with optics for the LCLS, and the...
For new astrophysics X-ray observatories like the Advanced Telescope for High ENergy Astrophysics (ATHENA), mirror surfaces of several hundred m² are required. As such an area is not achievable with a single mirror in space, the silicon pore optics (SPO) technology will be utilized. In the PTB laboratory at BESSY II, two dedicated beamlines are in use for their characterization with...
In most synchrotron applications, X-ray mirror slope specification is an important parameter for applications using a partially coherent X-ray beam. The slope error is typically specified at the sub 100 nrad RMS for mirrors up to 1000 mm long by 50 mm wide. For applications using diffraction-limited X-ray beams, height specification is a more relevant parameter to maintain and focus the beam...
Multilayer coating on top of high line density blazed gratings can increase its diffraction efficiency up to one order of magnitude for a selected diffraction order. In combination with multilayer coated pre-mirror in plane grating monochromator (PGM) the total instrument transmission can be increased in hundreds of times. In our developments on multilayer-coated blazed gratings (MLBG) we have...
Driven by the fast development of the new generation storage ring and free-electron laser facilities, X-ray mirrors with nanometer figure accuracy, complex shape and large size are widely demanded. These optics are being developed in Tongji University using stitching interferometry and ion beam figuring technique. Stitching interferometry is commonly used for the 2-D figure metrology of X-ray...
