Isomer 178m2Hf prepared by using α particles to bombard a natural ytterbium target and analysis ofhigh purity Ge γ spectrum

Abstract

178m2Hf isomer is of great importance in science and application. Using natural ytterbium bombarded by α particles to produce 178m2Hf through 176Yb (α, 2n) 178m2Hf nuclear reaction may be a low-cost way. Three natural ytterbium targets of about 200 μ m in thickness are fabricated by magnetron sputtering of natural Yb onto copper substrates, and then irradiated with 30 MeV, 50 μ A α beam in the CS-30 cyclotron for about 50 hours. After cooling, Hf is isolated from one target through chemical isolation. Gamma spectra of two targets and the isolated Hf sample are measured with high purity Ge detector. Overlapping peaks of the complex spectrum are separated by using Gaussian multi-peak fitting. The content of 178m2Hf nuclide is identified to be 1012 orders of magnitude in each target, and 1011 orders of magnitude in the purified sample from chemical isolation. The content values of other radioactive nuclides (175Hf, 172Lu, 172Hf, 177Lu, 173Lu ) in targets are also measured.