16BMD –A Versatile Static Compression Beamline at HPCAT

HPCAT 16-BM-D beamline is dedicated for static compression studies using a variety of synchrotron x-ray techniques including micro-XRD, XAS, and micro-tomography imaging. The beamline utilizes a fixed-exit geometry of the monochromatic beam with covered energy range of 6-60 keV and a robust energy scanning capability with high fidelity energy calibration. Recently, the monochromator has been upgraded with a dual-mode double crystal monochromator (DCM) and double multilayer monochromator (DMM) combined in a single chamber. The DCM consists of Si 111 single crystals in a pseudo channel-cut geometry, providing ΔE/E = 1.45×10^-4 energy resolution for X-ray absorption spectroscopy and micro-XRD. The DMM is made of 400 layers of Ni-B₄C bilayer with 30 Å d-spacing, providing ~1.3% bandwidth pink beam with ~60-90 times DCM intensities that benefits fast scanning X-ray diffraction imaging and parallel beam tomographic imaging. With the new choices of incident beam, a variety of static compression experiments can be conducted combined with resistive heating and cryo-cooling sample environments. A detailed specification of the dual-mode monochromator and some selected case studies are presented.