PRELIMINARY STUDIES OF DELAYED NEUTRON EMISSION FROM SEPARATED ISOTOPES OF GASEOUS FISSION PRODUCTS

摘要

An on-line isotope separator system is described which was de-signed for use in studies of short-lived activities produced at a reactor. Detailed description is presented for the use of this system in the study of radioactive decay and delayed neutron emission for gaseous fission products formed in fission of U-235. Experiences -with sample con-figuration and characteristic limitations of the system (such as half-life) are discussed. Preliminary results are presented regarding the as¬signment of delayed neutron precursors to mass number (by neutron counting) and element (by half-life determination). At present, definite assignments have been made for 91Kr, 92Kr, 93Rb, and 93Kr. Indica¬tions of delayed neutron emission for masses 141 and 142 are discussed. Future plans for delayed neutron studies are discussed and nuclear structure studies in progress are outlined.