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Antares achieves zero-power criticality at INL
Leveraging more than $140 million in private capital fundraising, over 322,000 square feet of operational manufacturing space, and multifaceted partnerships with the Departments of Energy and Defense, reactor start-up Antares has become the first company involved in the Reactor Pilot Program to achieve zero-power fueled criticality—a full month ahead of the July 4 deadline set by President Trump’s Executive Order 14301.
This milestone, announced yesterday, was achieved with the company’s Mark-0: a sodium heat-pipe-cooled, TRISO-fueled microreactor. The Mark-0 is a forerunner to the company’s flagship design, which it calls the R1. For Antares, this development represents a key validation of its reactor physics, control systems, and supply chain.
M. Reinhart et al.
Fusion Science and Technology | Volume 63 | Number 1 | May 2013 | Pages 201-204
doi.org/10.13182/FST13-A16905
Articles are hosted by Taylor and Francis Online.
In this work we investigate the applicability of several optical emission spectroscopy methods to measure the electron density and temperature in deuterium plasma in the linear plasma generator PSI-2. The spectroscopy measurements are realized by an imaging spectrometer which delivers radial profiles of the emission lines. With the application of an inverse Abel transformation, spatially resolved measurements are obtained.The spectroscopy methods divide into two groups: The measurement of ne by Balmer line ratios and by the rotational temperature of molecules is only suitable for ionizing plasmas; the measurement of ne by the Stark broadening of Paschen lines and of Te by Paschen line ratios is only applicable for recombining plasmas.For the evaluation of these methods, different plasma conditions are produced in PSI-2. The plasma generator is capable of producing deuterium plasmas with electron densities of up to 1013 cm-3 and electron temperatures of up to 20 eV. Additional measurements with a Langmuir double probe are conducted for comparison with the spectroscopy measurements.A collisional-radiative model in the Yacora code is used to compare measured Balmer line emissions with the calculation and to investigate which reaction channels influence the recombination in PSI-2.
