HALF-LIVES AND DELAYED NEUTRON EMISSION PROBABILITIES OF SHORT-LIVED RB-PRECURSORS AND CS-PRECURSORS

Half-lives and delayed-neutron emission probabilities (Pn) of short-lived Rb and Cs precursors in the mass chains 94-98 and 143-147 were measured. Sources of isotope separated nuclides were obtained from the on-line mass-separator OSTIS installed at the Grenoble high-flux reactor. A new Pn-value of (25.4±3.2)% is given for the (214±30) ms147Cs; the Pn-values of nine alkali precursor nuclides were redetermined: (2,730±20) ms94Rb with (9.7±0.5)%, (377 ±6)ms95Rb with (8.6±0.5)%, (197±5)ms96Rb with (12.5±0.9)%, (171±4) ms97Rb with (25.2±1.8)%, (114±13)ms98Rb with (18.4±2.9)%, (1,765±30)ms143Cs with (1.74 ±0.12)%, (1,000±10)ms144Cs with (2.95±0.25)%, (616±20) ms145Cs with (12.2±0.9)%, (325±10)ms146Cs with (13.2±0.8)%. The results are compared with the existing data, and the Pn-values are discussed within some simple model predictions. © 1979 Springer-Verlag.