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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.
H. Takahashi, A. Okamoto, Y. Kawamura, T. Kumagai, A. Daibo, S. Kitajima
Fusion Science and Technology | Volume 63 | Number 1 | May 2013 | Pages 404-407
doi.org/10.13182/FST13-A16969
Articles are hosted by Taylor and Francis Online.
Keeping compatibility between steady state gas puffing and stable radio frequency (RF) discharge, helium recombining plasma production was achieved in an RF plasma device. In this experiment, axial position of orifice, which suppresses backflow of secondary gas, was modified to increase electron density at a test region. Changing neutral pressure at the test region from 11 Pa to 21 Pa, the electron temperature, the electron density and the wavelength spectrum were measured. The electron temperature decreased with increasing neutral pressure and finally becomes about 3 eV. The electron density shows similar pressure dependence as the electron temperature. When the neutral pressure increases to 15 Pa, the line spectra from highly excited helium atoms were clearly observed. The electron temperature estimated from these line spectral intensities is about 0.05 eV, which indicates that the electron density reduction is caused by volumetric recombination occurring at the periphery of the plasma column.