Development of a rapid-transit system for precision nuclear physics measurements

Finch, S. W.; Gooden, M. E.; Hagmann, C.; Howell, C. R.; Krishichayan, None; Ramirez, A. P. D.; Silano, J. A.; Stoyer, M. A.; Tonchev, A. P.; Tornow, W.; Wilhelmy, J. B.

doi:10.1016/j.nima.2021.166127

DOE OSTI · 1835240

Development of a rapid-transit system for precision nuclear physics measurements

Finch, S. W.·Gooden, M. E.·Hagmann, C.·Howell, C. R.·Krishichayan, None·Ramirez, A. P. D.·Silano, J. A.·Stoyer, M. A.·Tonchev, A. P.·Tornow, W.·Wilhelmy, J. B.

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Abstract

A Rapid Belt-driven Irradiated Target Transfer System, named RABITTS, was developed for use at the Triangle Universities Nuclear Laboratory. This system allows for cyclic activation with neutron or photon beams, and measurement of reaction products using γ-ray spectroscopy. Both a 1 meter and 10 meter transfer system have been developed with transit times as low as 0.4 and 1.0 seconds, respectively. The systems are deployed at the tandem accelerator laboratory for use with monoenergetic neutron beams, and at the High-Intensity γ-ray Source facility for activation using photon beams. A detailed characterization of the systems’ performance and sensitivity is presented. In order to produce the highest accuracy cross-section data, a model for calculating corrections to cyclic activation with variable beam flux is developed and presented. We have commissioned these systems by measuring 197m Au, where we report a measured half-life of 7.73 ± 0.05 s and a 197 Au(n, n') 197m Au isomer production cross of 628 ± 28 mb at neutron energy E n = 2.0 MeV. In addition, we measured 90m Zr, where we report a measured half-life of 799.7 ± 8.0 ms and a 90 Zr(n, n') 90m Zr isomer production cross of 180 ± 12 mb at E n = 4.6 MeV. Furthermore, these measured half-lives are in excellent agreement with the evaluated values and the cross-section measurements are performed at previously unmeasured incident neutron energies.

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38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY 47 OTHER INSTRUMENTATION 73 NUCLEAR PHYSICS AND RADIATION PHYSICS Cyclic activation Digital electronics Neutron inelastic scattering Neutron-induced cross sections Nuclear isomers γ-ray spectroscopy

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Finch, S. W., Gooden, M. E., Hagmann, C., Howell, C. R., Krishichayan, None, Ramirez, A. P. D., Silano, J. A., Stoyer, M. A., Tonchev, A. P., Tornow, W., Wilhelmy, J. B.. 2021-12-11. Development of a rapid-transit system for precision nuclear physics measurements. https://doi.org/10.1016/j.nima.2021.166127

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