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The deadline arrives: Checking in on the Reactor Pilot Program
On May 23, 2025, President Trump signed Executive Order 14301, “Reforming Nuclear Reactor Testing at the DOE,” which instructed the Department of Energy to create a Reactor Pilot Program (RPP)—a new system in which companies could pursue DOE authorization to build and test their first-of-a-kind nuclear technologies. EO 14301 set an ambitious goal for that program: three reactors achieving criticality by July 4, 2026.
Bruno Bärs, Esko Markkanen
Nuclear Science and Engineering | Volume 48 | Number 2 | June 1972 | Pages 202-210
Technical Paper | doi.org/10.13182/NSE72-A22471
Articles are hosted by Taylor and Francis Online.
Rossi-alpha auto- and cross-correlation measurements on a large subcritical assembly using an in-core neutron detector and in-core and ex-core photon detectors are reported. The correlation amplitude and the main relaxation constant were determined in each measurement. The relaxation constants ( = 4090 1/sec) and the nine relative correlation amplitudes obtained were used to determine four space damping factors and some basic parameters describing the sources of correlated fluctuations.By utilizing some basic fission parameters (⟨v⟩, ⟨v2⟩, spontaneous fission probability) and the effective multiplication factor (k = 0.788) from pulsed-neutron source measurements or from computations, estimates for the prompt-neutron lifetime (l = 53.2 µsec), the equivalent number of free neutrons (⟨y0⟩= 5.24) in the reactor, the mean fission rate (αf⟨y0⟩ = 73 800 1/sec) and the efficiency (€nl = 8.1 × 10-4) of the neutron detector could further be determined.The results verify the applicability of the gamma observation technique in reactor noise measurements as a substitute and a complement to noise measurements via neutron detection.
