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A year in orbit: ISS deployment tests radiation detectors for future space missions
The predawn darkness on a cool Florida night was shattered by the ignition of nine Merlin engines on a SpaceX Falcon 9 rocket. The thrust of the engines shook the ground miles away. From a distance, the rocket appeared to slowly rise above the horizon. For the cargo onboard, the launch was anything but gentle, as the ignition of liquid oxygen generated more than 1.5 million pounds of force. After the rocket had been out of sight for several minutes, the booster dramatically returned to Earth with several sonic booms in a captivating show of engineering designed to make space travel less expensive and more sustainable.
Cheol Ho Pyeon, Ryota Katano, Akito Oizumi, Masahiro Fukushima
Nuclear Science and Engineering | Volume 197 | Number 11 | November 2023 | Pages 2902-2919
Regular Research Article | doi.org/10.1080/00295639.2023.2172311
Articles are hosted by Taylor and Francis Online.
Sample reactivity and void reactivity experiments are carried out in the solid-moderated and solid-reflected cores at the Kyoto University Critical Assembly (KUCA) with the combined use of aluminum (Al), lead (Pb), and bismuth (Bi) samples, and Al spacers simulating the void. MCNP6.2 eigenvalue calculations together with JENDL-4.0 provide good accuracy of sample reactivity with the comparison of experimental results. Also, experimental void reactivity is attained by using MCNP6.2 together with JENDL-4.0 and ENDF/B-VII.1 with a small relative difference between experiments and calculations. Uncertainty in sample reactivity and void reactivity due to the ENDF/B-VII.1 Al, Pb, and Bi nuclear data is quantified using sensitivities calculated by the ksen card in MCNP6.2 and covariances provided by SCALE6.2. A series of reactivity analyses with the Al spacer simulating the void demonstrates the means of analyzing the void in the solid-moderated and solid-reflected cores at KUCA.