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The 89Y(n,γ) reaction: Radiative cross sections and the decay of 90Ym
1Department of Physics, Oregon State University, Corvallis, OR, 97331, USA.
Abstract:
The activity 90Ym was produced by radiative neutron capture on targets of mono-isotopic 89Y at several different reactor sites. By observing the γ rays emitted in the decay of 90Ym, the thermal neutron cross section was deduced to be 1.02(1) mb, and the resonance integral was deduced to be 7.82(19) mb or 7.35(15) mb at 2 different reactor sites. The energies of the 3 γ rays emitted in the 90Ym decay were measured to be 202.539(10), 479.532(10), and 682.03(4) keV by comparison with the energies of lines in well-known calibration sources. The half-life of the 90Ym decay was determined to be 3.178(12) h. The cross sections are discussed in the context of a statistical model of radiative capture.
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