Neutron capture cross-section measurement of lead-204 by mass spectrometry

Nakamura, Shoji  ; Kimura, Atsushi   ; Endo, Shunsuke   ; Shizuma, Toshiyuki*; Shibahara, Yuji*

In recent years, research has been advanced on lead-cooled fast reactors and accelerator drive systems, and it is required to improve the accuracy of the neutron capture cross section of Pb isotopes. Although Pb has a small natural abundance, it is of importance because it produces the long-lived radionuclide Pb (17.3 million years) by neutron capture reaction. However, it is difficult to measure its cross section by a conventional activation method using a nuclear reactor because the induced radioactivity of Pb is weak. Hence, the cross-section measurement was performed by applying mass spectrometry. This presentation gives the details of the experiment and the results obtained in the neutron capture cross-section measurement of Pb using mass spectroscopy.