By Dr. Luis Delgado-Aparicio - Head of Advanced Projects at the Princeton Plasma Physics Laboratory (PPPL).
The WEST superconducting tokamak in France features a full tungsten environment and is equipped with actively cooled walls providing valuable input for future operation of nuclear fusion reactors. Versatile multi-energy soft and hard x-ray pinhole cameras have been developed, calibrated, deployed and operated for long-pulse plasmas at WEST. These innovative imaging diagnostic leverages a pixelated Si and CdTe x-ray detectors capable of independently adjusting the lower energy threshold for photon detection on each pixel. Central electron temperature values are derived by modeling the slope of continuum radiation, extracted from ratios of inverted radial emissivity profiles across multiple energy ranges, without relying on a-priori assumptions of plasma profiles, magnetic field reconstructions, high-density limitations, or shot-to-shot reproducibility. Recent breakthroughs include the temporal evolution measurement of central temperature in quasi non-inductive scenarios with a stationary central electron temperature of ~4.5 keV (> 50 million degrees ℃) for up to 6 minutes with a total injected energy of up to 1.14 GJ. These results - among others – force our community to bridge the gap between fusion science and technology and high-energy physics using detector technology developed for high-luminosity experiments at CERN capable of withstanding neutron fluences up to 1016 n/cm2/MeV; Si3D, SiC, Diamond and GaN are materials presently being considered.
About the speaker
Dr. Luis Felipe Delgado-Aparicio, a native of Lima-Peru, earned a bachelor and licentiate degrees in physics from the Pontificia Universidad Catolica del Peru in 1997, and a master’s degree in Astrophysics from Princeton University in 2001. He obtained a second master’s in physics from The Johns Hopkins University (JHU) and received his PhD in physics also from JHU in 2007. Most of his nuclear fusion work was carried out at the NSTX experiment at the Princeton Plasma Physics Laboratory (PPPL). Luis Felipe became a scientist at JHU right away, but was soon recruited by Princeton University in 2009 to spent four years as a visiting scientist at The Plasma Science and Fusion Center (PSFC) at the Massachusetts Institute of Technology (MIT) in Cambridge, MA. Since his return to Princeton in 2013, Luis Felipe has won few awards in plasma physics and nuclear fusion including the Department of Energy (DOE) Early Career Award in 2015, the General Atomics Torkil Jensen Award in 2016, the President’s International Fellowship Initiative (PIFI) award from the Chinese Academy of Sciences (CAS) in 2018 and a Measurement Innovation Award from DOE also in 2018. Luis Felipe has lead experiments at the four major fusion experiments in the USA, and designs and builds nuclear fusion diagnostics for universities and national laboratories in the USA, China, France, Japan, and the international community at ITER, a 30B$ nuclear reactor being built in the south of France. He has written and published more than 140 scientific articles having more 1600 citations. Luis Felipe lives in Princeton, NJ with his family.
