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November 9–12, 2025
Washington, DC|Washington Hilton
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NNSA furloughs 1,400 employees, pays contractors until end of month
After nearly three weeks of a government shutdown, the Department of Energy’s National Nuclear Security Administration has furloughed 1,400 employees and has retained 400 as essential employees who will continue working without pay.
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.
