High temperature transmission measurements of graphite, SiC, ZrC, and MgO

This research aims to measure the temperature-dependent transmission, i.e. total cross sectio, of graphite, silicon carbide (SiC), zirconium carbide (ZrC), and magnesium oxide (MgO) using the VESUVIO beamline at ISIS. These materials are crucial for advanced high-temperature nuclear reactor designs, as identified in recent US DOE/NRC collaborations. Current Evaluated Nuclear Data File (ENDF) libraries, which provide critical data for reactor design and safety analysis, contain inaccuracies in thermal scattering laws (TSLs) due to modeling errors, especially for materials like nuclear graphite with varying porosities. Our preliminary work includes room temperature transmission measurements of different grades of nuclear graphite, and phonon spectrum measurements at 5 K and 296.3 K for SiC, ZrC, and MgO, as well as atomistic calculations to predict their behavior at elevated temperatures. We propose to extend these measurements up to 900 C to provide accurate experimental data for validating and improving TSLs in ENDF.