HIPPO - High-Pressure-Preferred Orientation is the first third-generation neutron time-of-flight powder diffractometer constructed in the United States. It achieves very high neutron count rates by virtue of a short (9 m) initial flight path on a high-intensity water moderator and 1200 3He detector tubes covering 4.8 m2 of detector area from 40° to 150° in scattering angles.
HIPPO was designed and manufactured as a joint effort between LANSCE and the University of California with the goal of doing world-class science by making neutron powder diffractometry an accessible tool to the national user community.
D-spacing ranges from 0.12-4.80 Å (1.31-52.4 Å-1) to 1.2-47.5 Å (0.13-5.3 Å-1) are available to support studies of crystal orientation distribution (texture), amorphous solids, liquids, magnetic diffraction, small crystalline samples, and samples subjected to non-ambient environments such as temperature, pressure, or uniaxial stress.
The exceptionally high data rates of HIPPO also make it useful for time-resolved studies. In addition to the standard ancillary equipment (100-specimen sample changer, closed-cycle He refrigerator, furnace), HIPPO has unique high-pressure anvil cells capable of achieving pressures of 30 GPa at ambient and high (2000 K) temperatures with samples up to 100 mm3 in volume. The uniaxial stress-rig CRATES, built by the Technical University Hamburg-Harburg, Germany, allows the study of crystal lattice strains and texture changes in situ during deformation.
HIPPO's sample chamber also accomodates user-provided sample environments.