State-of-the-art X-ray and optical diagnostics are available at the DCS to enable time-resolved, in-situ, atomistic-scale investigations of condensed matter phenomena under dynamic compression.
Time-resolved X-ray diffraction to measure atomistic-scale changes during dynamic compression and deformation. Phenomena that can be examined include structural transformations, texture evolution, deformation induced anisotropic strains, and evolution of microstructural heterogeneities.
- Indirect detection X-ray phosphor-based diffraction detectors are capable of recording four frames of 100-ps-duration X-ray images with an interframe spacing of 153.4 ns, to match the X-ray period in the 24-bunch mode (75 mm Diameter Active Area, High X-ray QDE up to 35 keV.)
- Powder diffraction measurements are obtained using a pink X-ray beam with energies extending up to 35 keV and X-ray spectral bandwidths of a few percent. Broadband X-rays are also available for Laue diffraction measurements on single crystals. A monochromatic beam (~0.01% spectral bandwidth) can be used for high-resolution diffraction measurements on single crystals.
Time-resolved, high-spatial-resolution (~5 µm), phase contrast imaging or absorption radiography measurements to obtain a sequence of spatially resolved images during dynamic events. Such imaging measurements can be used to observe the evolution of micro- and meso-scale changes during dynamic loading.
- Scintillator-based, indirect-detection detectors are optimized for 24-bunch mode and capable of recording four frames per experiment with an interframe spacing of 153.4 ns (4-frame, ~5 μm Spatial Resolution, High X-ray QDE up to 35 keV).
Both the imaging and diffraction detectors are capable of recording four frames of 100-ps-duration X-ray images with an interframe spacing of 153.4 ns (corresponding to the 24-bunch mode).
Optical Diagnostics for Time-Resolved Continuum Measurements
Time-resolved continuum diagnostics, such as single-point and multi-point laser velocimetry (e.g., VISAR and PDV), are available for simultaneous acquisition of continuum measurements along with the X-ray diffraction and/or imaging measurements.
Particle velocity measurements are obtained via optically coupled rack mounted VISAR or PDV systems located in the DCS Instrumentation Room. The custom made interferometers are highly versatile and stable, offering multiple Velocity-Per-Fringe (VPF) capabilities for the VISAR systems and continuous PDV upshifting capability. Each interferometer includes gated and CW laser sources, high speed and high gain detectors, multiple high speed digitizers, and multiple fiber optic lines to each end station. The interferometry systems can be controlled remotely from the impact facility control rooms. Interferometry analysis software support is provided.
The following optical diagnostics are available at the DCS:
- PDV System: 12 Channels with Upshifting Capability, with 5 W IPG laser with RIO seed laser
- VISAR System: 8 fixed VPF Push-Pull VISARs ranging from 70 to 1600 m/s/fr, up to 8 probe points with single VPFs, up to 4 probe points with dual-VPFs, 6 W VERDI laser source
- Dedicated Optical Diagnostic Digitizers
- 8 digitizer channels (8 GHz and 12.5 GHz) for PDV
- 8 digitizer channels (1 GHz) for VISAR