Fast-neutron activation of long-lived nuclides in natural Pb

• Published in: Astroparticle physics Vol. 64; no. C; pp. 34 - 39
• Main Authors: Guiseppe, V.E., Elliott, S.R., Fields, N.E., Hixon, D.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.04.2015; Elsevier
• Subjects: Activated; Activation; Cosmic ray; Double-beta decay; Earth surface; Lead; Lead (metal); Mercury (metal); Neutron activation; Neutron flux; Nuclides; Sea level; USA, New Mexico, Los Alamos; Lead; Cosmic ray; Neutron activation; Double-beta decay
• ISSN: 0927-6505; 1873-2852
• DOI: 10.1016/j.astropartphys.2014.11.002

We measured the production of the long-lived nuclides 207Bi, 202Pb, and 194Hg in a sample of natural Pb due to high-energy neutron interactions using a neutron beam at the Los Alamos Neutron Science Center. The activated sample was counted by a HPGe detector tomeasure the amount of radioactive nuclides present. These nuclides are critical in understanding potential backgrounds in low background experiments utilizing large amounts of Pb shielding due to cosmogenic neutron interactions in the Pb while residing on the Earth’s surface. By scaling the LANSCE neutron flux to a cosmic neutron flux, we measure the sea level cosmic ray production rates of 8.0±1.3atoms/kg/day of 194Hg, 120±25atoms/kg/day 202Pb, and <0.17±0.04atoms/kg/day 207Bi.