Radiochemical Determination of Long-Lived Radionuclides in Proton-Irradiated Heavy-Metal Targets: Part I-Tantalum

摘要

In this study, distillation, precipitation, and ion-exchange methods were chosen for the separation of the long-lived beta-emitters I-129, Cl-36 and the alpha-emitters Dy-154, Gd-148, Gd-150, and Sm-146 from Ta targets irradiated with protons up to 2.6 GeV to determine their production cross sections. Measurements of I-129/I-127 and Cl-36/Cl-35 ratios were performed with accelerator mass spectrometry. After separation of the lanthanides, the molecular plating technique was applied to prepare thin samples to obtain highly resolved alpha-spectra. Autoradiography and focused ion beam/scanning electron microscopy techniques were used to characterize the lanthanide deposited layer. Experimental cross-section data are compared with theoretical predictions obtained with INCL++ and ABLA07 code, and a satisfactory agreement is observed.