Alumnus' Diagnostic Research Earns Cover Spot
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Research from a Department of Energy National Nuclear Security Administration Stewardship Science Graduate Fellowship (DOE NNSA SSGF) recipient provided the featured cover image for a recent American Institute of Physics journal.
The November 2016 AIP Review of Scientific Instruments (from the Proceedings of the 21st Topical Conference on High-Temperature Plasma Diagnostics) displayed X-ray radiograph images captured by Hong Sio’s Particle X-ray Temporal Diagnostic (PXTD) instrument. Sio, A DOE NNSA SSGF recipient from 2012 to 2016, developed the tool as part of his doctoral thesis work at the Massachusetts Institute of Technology.
The PXTD measures nuclear products and X-rays produced in inertial confinement fusion (ICF) and high energy density plasma experiments. In indirect-drive ICF, powerful lasers generate X-rays that crush a sphere about the size of a pea. The capsule is filled with a frozen mixture of two hydrogen isotopes, deuterium and tritium. If all goes well, the X-rays squeeze the isotopes so tightly their nuclei fuse, releasing tremendous energy. A similar process, on a grand scale, fuels the sun and other stars.
![Review of Scientific Instruments cover, November 2016 Review of Scientific Instruments cover, November 2016](/nnsassgf/images/website/Fellow17_Sio_Diagnostic_cover.jpg)
The PXTD is designed to help understand what’s happening in ICF and similar experiments. In research on the OMEGA laser facility at the University of Rochester, PXTD took time-resolved, high-precision measurements of multiple products from nuclear reactions happening in the target. The diagnostic simultaneously measured X-rays the target emitted over time.
The instrument, Sio wrote in the journal article, has precision measured in tens of picoseconds (10-11 seconds) between the nuclear and X-ray signals. It allows, for the first time, accurate and simultaneous measurement of the peak X-ray emission time and peak nuclear production time, their time differences, and other experimental properties.
Sio was invited to present the paper at the high-temperature plasma diagnostics conference in June 2016 at Madison, Wisconsin. Sio also will make a presentation on the diagnostic and associated data analysis at NNSA headquarters in Washington on May 9. His doctoral advisor is Richard Petrasso.