Spallation neutron source target station design, development, and commissioning

Neutron scattering studies of spin-phonon hybridization and superconducting spin gaps in the high-temperature superconductorLa2−x(Sr,Ba)xCuOWagman1, Carlo2, Gaudet3 et al. 2016Phys. Rev. B13921View full textAdd to dashboardCite

“…Both are direct geometry chopper instruments and use the same ambient temperature moderator for their incident neutrons 35 . The single crystal samples were mounted in closed cycle refrigerators allowing measurements to probe the approximate temperature range from 5 to 300 K with a temperature stability of ∼ 0.1 K. All measurements were performed with single crystal samples aligned such that their HHL scattering plane was horizontal.…”

Recent Status of the Pulsed Spallation Neutron Source at J-PARC

“…We have also improved structure of the front end of the target vessel, the beam injection portion, from single wall to double wall with a gap of 2 mm [2,8] to suppress cavitation growth by making high-speed mercury flow in the narrow gap. Note that the mercury target of the Spallation Neutron Source at Oak Ridge National Laboratory [9] had included a double-walled narrow channel structure, but it is replaced three times during annual operation with the rated power of 1.4 MW at 60 Hz.…”

Gamma-spectrometric measurement procedure for a clearance concept of radioactively contaminated mercury from nuclear facilities

“…A liquid material can easily be mixed and thus ensures a good heat distribution, while at the same time an embrittlement of the target material (as in solid materials) is avoided. Mercury is thus used in spallation targets in the Japan Spallation Neutron Source (JSNS), Tōkai, Japan, and in the Spallation Neutron Source (SNS), Oak Ridge, Tennessee [28][29][30][31][32][33][34][35]. To the best of our knowledge, no final disposal route for the mercury from this process has been approved.…”

“…Simulations have been performed to determine possible activation products that could be formed in this spallation target and lead to a variety of different radionuclides, including, next to radioactive isotopes of platinum, gold, iodine, etc., the formation of radioactive mercury isotopes that could not be separated from the bulk of the elemental mercury in the target. This formation of radionuclides that cannot be separated from the mercury leads to the possibility that the whole mercury from this facility needs to be disposed of as radioactive waste as a decontamination of the mercury might not be possible [31][32][33].…”