ANL, Lemont, Illinois, USA
As part of the Advanced Photon Source Upgrade (APS-U) project, the Coherent Surface Scattering Imaging (CSSI) [1] instrument is currently being developed. One of the most important components of the CSSI instrument at the 9-ID beamline of the APS-U, the Kirkpatrick-Baez (K-B) mirror system, will focus hard X-rays to a diffrac-tion-limited size of 500 nanometers at a working distance of 550 mm. High angular stability (19 nrad for the hori-zontal mirror and 14 nrad for the vertical mirror) is speci-fied no just for the focused beamsize but, more important-ly, to ensure the beam stability at the detector position that is up to 24 m from the K-B mirrors. A large sample-to-detector distance (up to 23 m), one of the beamline’s unique features for achieving a sufficient coherent-imaging spatial oversampling, requires sample angular stability of 50 nrad. In CSSI scattering geometry, the vertically placed sample reflects X-rays in the horizontal direction at an extremely shallow angle. The design in-cludes two high-precision rotary stages for sample pitch (vertical axis) and yaw (horizontal axis). The current design of instrument’s nano-positioning stages [2] and metrology required to satisfy the stability and positioning requirements are discussed in this paper.
*T. Sun et al., Nat. Photonics 6, 586 (2012).
**D. Shu et al., this conference.
MAX IV Laboratory, Lund University, Lund, Sweden
ForMAX is a new beamline at the MAX IV Laboratory for multi-scale structural characterization of hierarchical materials from nm to mm length scales with high temporal resolution. This is achieved by combining full-field microtomography with small- and wide-angle X-ray scattering (SWAXS) in a novel manner. The principal components of the endstation consist of two units of beam conditioning elements, a sample table, an evacuated flight tube and a detector gantry. The beam conditioning units include a diamond vacuum window, an attenuator system, a fast shutter, a slit collimation system, two sets of compound refractive lenses, three X-ray beam intensity monitors, a beam viewer and a telescopic vacuum tube. The sample table has been optimized with respect to flexibility and load capacity, while retaining sub-micron resolution of motion and high stability performance. The nine metre long and one metre diameter evacuated flight tube contains a motorised detector trolley, enabling the sample-detector position for small-angle X-ray scattering (SAXS) to be easily adjusted under vacuum conditions. Finally, a two metre high and two metre wide granite gantry permits independent and easy movement of the tomography microscope and wide-angle X-ray (WAXS) detector in and out of the X-ray beam. To facilitate propagation-based phase-contrast imaging and mounting of bulky sample environments, the gantry is mounted on motorized floor rails. All these characteristics will allow to combine multiple complementary techniques sequentially in the same experiment with fast efficient switching between setups. The ForMAX endstation is presently in the design and construction phase, with commissioning expected to commence early 2022.
BNL, Upton, New York, USA
Open Platform and Liquids Scattering (OPLS) is a new experimental station recently built and currently being commissioned at the Soft Matter Interfaces (SMI) beamline 12-ID at NSLS-II. The new instrument expands SMI’s beamline scientific capabilities via the addition of X-ray scattering techniques from liquid surfaces and interfaces. The design of this new instrument, located inside the 12-ID beamline shielding enclosure (hutch B), is based on a single Ge (111) crystal deflector, which bounces the incident x-ray beam downward towards a liquid sample which must be maintained in a horizontal orientation (gravity-driven consideration). The OPLS instrument has a variable deflector-to-sample distance ranging from 0.6 m to 1.5 m. X-ray detectors are mounted on a 2-theta scattering arm located downstream of the sample location. The 2-theta arm is designed to hold up to three X-ray detectors, with fixed 2-theta angular offsets, each dedicated to a different X-ray technique such as X-ray reflectivity, grazing-incidence X-ray scattering, and small- and wide-angle X-ray scattering. Currently, the OPLS experimental station intercepts the SMI beam that otherwise propagates to the experimental endstation located in hutch C and can be retracted to a ’parking’ position laterally out of this beam to allow installation of a removable beam pipe that is needed to support operations in hutch C. The design of OPLS is flexible enough to quickly adapt to a planned future configuration of the SMI beamline in which a OPLS is illuminated separately from the main SMI branch via a second, canted undulator source and a separate photon delivery system. In this future configuration, both branches will be able to operate independently and simultaneously.
ANL, Lemont, Illinois, USA
The X-ray Photon Correlation Spectroscopy (XPCS) beamline at the Advanced Photon Source (APS) has been selected as one of the nine feature beamlines being de-signed to take advantage of the increase in coherent flux provided by the APS Upgrade. The 8-ID-E enclosure at the beamline will have a dedicated instrument for per-forming Wide Angle XPCS (WA-XPCS) measurements across a range of length and time scales. The instrument will feature a high-stability 6-circle diffractometer, a moveable Long Distance Detector Positioner (LDDP) for positioning a large pixel array detector, and a removable flight path assembly. For intermediate sample to detector distances of 1.5 to 2 meters, a large pixel array detector will be positioned on the diffractometer detector arm. For longer sample to detector distances up to 4 meters, an horizontal scattering geometry will be utilized based on the LDDP to position a second large pixel array detector. The LDDP will consist of a large granite base on which sits a combination of motorized stages. The base will sit on air casters that allow the LDDP to be coarsely posi-tioned manually within the enclosure. Final positioning of the detector will be achieved with the mounted stages. The spatial relationship between the sample and the free moving LDDP will be monitored using a laser tracking system. A moveable flight path will be supported by the diffractometer arm and a mobile floor support to mini-mize air scattering while using the LDDP. The WA-XPCS instrument has been designed with users and beamline staff in mind and will allow them to efficiently utilize the highly enhanced coherent beam provided by the APS Upgrade.