Spallation products distributed in a thick iron target bombarded by 3-Bev protons

Abstract

The distribution of several spallation products, covering a wide range of atomic number, has been measured in a thick iron target (30×30×90 cm) bombarded by 3-bev protons at the Brookhaven cosmotron. Measurements were made of the radioactivity of γ-, β-, and X-ray emitters, either directly or after chemical separation, in iron and nickel foils placed at different depths. Products such as Co isotopes in Ni and Fe55, Mn54, and Cr51 in Fe, which are close to the target mass, were produced in important amounts at large angles to the primary beam. Production of nuclides of lower A showed gradually better collimation, Na22 and Be7 showing the smallest spread. These data provide useful information on the production rates of cosmogenic nuclides in meteorites and on their variation with depth and size. The results of this experiment may be compared with the available meteorite data and with other calculations.