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2020 Review of the Instrument Suite for Spectroscopy at the Spallation Neutron Source and High Flux Isotope Reactor

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2020 Review of the Instrument Suite for Spectroscopy at the Spallation Neutron Source and High Flux Isotope Reactor 2020 Review of the Instrument Suite for Spectroscopy at the Spallation Neutron Source and High Flux Isotope Reactor September 17–18, 2020 CONTENTS CONTENTS .................................................................................................................................................... iii LIST OF FIGURES ........................................................................................................................................... xi LIST OF TABLES ......................................................................................................................................... xviii 1. Introduction to the Spectroscopy Suite at SNS / HFIR .......................................................................... 1 1.1 Recommendations from the 2017 Suite Review ........................................................................ 2 1.2 Triple-Axis Spectrometers ........................................................................................................... 3 1.3 Direct Geometry Spectrometers ................................................................................................. 4 1.4 Chemical Spectroscopy ............................................................................................................... 6 1.5 Upgrades and Developments ...................................................................................................... 8 Triple-Axis Spectroscopy ............................................................................................................. 8 Direct Geometry Spectroscopy ................................................................................................... 9 Chemical Spectroscopy ............................................................................................................. 10 1.6 Critical needs for new instruments ........................................................................................... 11 New instruments for HFIR ......................................................................................................... 11 New instruments for FTS .......................................................................................................... 12 New instruments for STS .......................................................................................................... 13 1.7 Software .................................................................................................................................... 14 Data Reduction ......................................................................................................................... 14 Data Acquisition ........................................................................................................................ 14 Data Visualization and Analysis ................................................................................................ 15 1.8 Staffing ...................................................................................................................................... 16 2. HFIR HB-1 Polarized Triple-axis Spectrometer Beamline Status and Planning Summary .................. 18 2.1 Overview/Current Status .......................................................................................................... 18 2.2 Scientific Focus .......................................................................................................................... 19 2.3 Scientific Highlights ................................................................................................................... 20 New capabilities in high-resolution neutron Larmor diffraction at ORNL. ............................... 20 High-resolution phonon energy shift measurements with the inelastic neutron spin echo technique. ........................................................................................................... 21 Dual nature of Magnetism in a uranium heavy-fermion system .............................................. 22 Origin of net magnetic moment in LaCoO3 ............................................................................... 23 Unique helical magnetic order and field-induced phase in trillium lattice antiferromagnet EuPtSi. ............................................................................................... 24 2.4 General User Program .............................................................................................................. 25 2.5 Update on Instrument Development Activities ........................................................................ 25 2.6 Sample Environment ................................................................................................................. 26 2.7 Software .................................................................................................................................... 26 2.8 Update on Impact of Discretionary Beamtime ......................................................................... 26 2.9 Outreach and Expansion Activities ........................................................................................... 26 2.10 Vision ......................................................................................................................................... 26 2.10.1 Near-term Vision (1-3 years) ........................................................................................ 26 2.10.2 Strategic Vision (3-10 years) and Alignment with NScD/ORNL Strategic Plans ........... 27 2.11 Funding/Resource Needs .......................................................................................................... 27 2.11.1 Future Funding Opportunities ..................................................................................... 27 2.12 Self-assessment ......................................................................................................................... 28 Strengths ................................................................................................................................... 28 iii Weaknesses (Limitations) ......................................................................................................... 28 Opportunities ............................................................................................................................ 28 Threats 28 2.13 Executive Summary ................................................................................................................... 29 2.13.1 Comparison of instrument specifications to similar instrument worldwide ............... 30 2.13.2 Comparison of sample environment capabilities with similar instruments worldwide .................................................................................................................... 31 2.13.3 Data and computing capabilities ................................................................................. 31 3. HFIR HB-3 Triple Axis Spectrometer Beamline Status and Planning Summary .................................. 33 3.1 Overview/Current Status .......................................................................................................... 33 Team Structure ......................................................................................................................... 33 3.2 Scientific Focus .......................................................................................................................... 34 3.3 Scientific Highlights ................................................................................................................... 35 Temperature dependence of low-E magnetic fluctuations in nearly optimally doped NaFe0.9785Co0.0215As ....................................................................................................... 35 Supersonic propagation of lattice energy by phasons in fresnoite .......................................... 36 f-Electron States in PrPd5Al2 ..................................................................................................... 37 Low-T anharmonicity and the thermal conductivity of cesium iodide ..................................... 38 Anharmonic Eigenvectors and Acoustic phonon Disappearance in Quantum Paraelectric SrTiO3 ........................................................................................................................... 39 3.4 General User Program .............................................................................................................. 40 3.5 Update on Instrument Development Activities ........................................................................ 41 Omega shielding around the sample position. ......................................................................... 41 Velocity Selector ....................................................................................................................... 42 New analyzer tank wedge lifter system .................................................................................... 42 3.6 Sample Environment ................................................................................................................. 42 3.7 Software .................................................................................................................................... 42 3.8 Impact of Discretionary Beam Time .......................................................................................... 43 3.9 Outreach and Expansion Initiatives .........................................................................................
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