We describe a novel cold neutron spectrometer under development at NIST optimized for wave vector resolved spectroscopy with incident energies between 2.1 meV and 20 meV and energy resolution from 0.05 meV (E i = 2.1 meV) to 3.0 meV (E i = 20 meV). By using a 1428 cm 2 double focusing PG (0 0 2) monochromator close to the National Institute of Standards and Technology (NIST) cold neutron source the instrument provides up to 5 × 10 8 neutrons cm −2 s −1 on a 8 cm 2 sample area. The measured performance is consistent with Monte Carlo simulations. The monochromating system, which includes radial collimators, three filters and a variable beam aperture, offers considerable flexibility in optimizing Q-resolution, energy resolution and intensity. The detector system will consist of an array of 20 channels which combined will subtend a solid angle of 0.2 sr. This is approximately a factor of 40 more than a conventional triple axis spectrometer. Each detector channel contains a vertically focusing double crystal analyzer system (DXAL) actuated by a single stepping motor. We find identical integrated reflectivity at approximately 10% coarser energy resolution for the 130 mosaic double bounce analyzer as compared to a conventional 25 analyzer at the same energy. The vertical focusing of the DXAL allows for smaller detectors for enhanced signal to noise with 8 • vertical acceptance. Options for post sample collimators and filters provide flexibility in the choice of scattered beam energy and wavevector resolution.

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We present a summary description of the 8th annual international Design and Engineering of Neutron Instruments Meeting (DENIM) which was held in North Bethesda, MD, USA, September 17–19, 2019. DENIM VIII was organized by the National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR) in combination with the University of Maryland (UMD). DENIM specifically addresses the unique field of neutron instrument engineering, a subcategory of neutron scattering science. DENIM is organized by engineers for engineers who share openly about what works and what doesn’t work in the life cycle design of an instrument used to analyze materials with neutrons. DENIM is held under the patronage of the International Society of Neutron Instrument Engineers which was formed in 2017. At DENIM VIII, there were 3 keynote talks, 29 additional presentations and 13 posters (presented to the plenary in a poster slam session). Attendees toured the unique labs at NIST including the NCNR. Four parallel knowledge sharing sessions helped attendees explore mutual challenges and solutions in the areas of Instrument Installation Survey and Alignment, Electrical Grounding, Choppers and Velocity Selectors, and 3D Printing.