182Hf is a long-lived radionuclide of particular interest for the early history of the solar system. The measurement of 182Hf has been performed with a 13-MV tandem accelerator (HI-13 ) mass spectrometry at China Institute of Atomic Energy(CIAE). In this work, 182Hf was produced through irradiating HfO2, enriched in 180Hf to 98.3%, with the high neutron flux of the heavy water research reactor at CIAE. After irradiation, the ratio of 182Hf/180Hf measured with a thermal ionization mass spectrometry was (1.628±0.011)χ10-6 in the sample. Standard samples with 182Hf/180Hf ratios of (4.45±0.05)χ10-8 and (4.40±0.05)χ10-10 were prepared using irradiated sample and enriched 180HfO2. Although the main interference to the detection, the stable isobar 182W, can be significantly reduced by using HfF5- beam, chemical separation is necessary. For chemical separation, the irradiated sample was prepared for chemical formation of HfF4, then it was dissolved in HF solution for column separation. The sample solution was loaded onto an anion exchange column, then Hf was eluted by HF and HCl solution, while W and Ta retained on the column. Tracer experiments showed that the average chemical yield of Hf was greater than 95%, and the decontamination factors for W and Ta both were larger than 1000. The formation of samples final used was HfF4 powder, the HfF5- beam was extracted from MC-SNICS ion source and Hf 9+ ions were analyzed at energy of 78 MeV. The HfF5- yield and 182Hf transmission efficiency were measured to be about 0.34% and 0.50% respectively in our AMS facility. The total efficiency for 182Hf measurement with our setup was about 1.7χ10-5. For identification, a golden-silicon surface barrier detector (as energy detector) combined with a time of flight detector was used. The energy spectra and flight time spectra of 182Hf have been obtained.
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