title: Measurements of activation induced by environmental neutrons using ultra low-level gamma-ray spectrometry.
abstract: The flux of environmental neutrons is being studied by activation of metal discs of selected elements. Near the earth's surface the total neutron flux is in the order of 10(-2) cm(-2)s(-1), which gives induced activities of a few mBq in the discs. Initial results from this technique, involving activation at ground level for several materials (W, Au, Ta, In, Re, Sm, Dy and Mn) and ultra low-level gamma-ray spectrometry in an underground laboratory located at 500 m.w.e., are presented. Diffusion of environmental neutrons in water is also measured by activation of gold at different depths.
authors.affiliation: EC-JRC-IRMM, Geel, Belgium.
authors.forename: M J
authors.initials: MJ
authors.lastname: Martínez Canet
authors.forename: M
authors.initials: M
authors.lastname: Hult
authors.forename: M
authors.initials: M
authors.lastname: Köhler
authors.forename: P N
authors.initials: PN
authors.lastname: Johnston
mesh_terms: D000186:Actinium; D008906:Mining; D011883:Radium / Q000032:analysis*; D013051:Spectrometry, Gamma / Q000379:methods; D013910:Thorium / Q000032:analysis*; D014501:Uranium; D014875:Water Pollutants, Radioactive / Q000032:analysis*
chemical_list: D014875:Water Pollutants, Radioactive; D014501:Uranium; D013910:Thorium; D000186:Actinium; D011883:Radium