Production and β decay of rp-process nuclei 96Cd, 98In and 100Sn
Abstract
The β-decay properties of the N=Z nuclei 96Cd, 98In and 100Sn have been studied. These nuclei were produced at the National Superconducting Cyclotron Laboratory (NSCL) by fragmenting a 120 MeV/nucleon 112Sn primary beam on a Be target. The resulting radioactive beam was filtered in the A1900 and the newly commissioned Radio Frequency Fragment Separator (RFFS) to achieve a purity level suitable for decay studies. The observed production cross sections of these nuclei are lower than predicted by factors of 10 to 30. The 100Sn production cross section is 0.25(15) pb, in sharp contrast with the 120 pb lower limit established at 63 MeV/nucleon incident energy of the same primary beam. The deduced half-life of 100Sn is 0.55+0.70-0.31 s, in agreement with previous measurements. Two β-decaying states in 98In were observed with measured half-lives of 47(13) ms and 0.66(40) s. The half-life of 96Cd, which was the last experimentally unknown waiting point half-life of the astrophysical rp-process, is 1.03+0.24-0.21 s. The implications of the experimental T1/2 value of 96Cd on the abundances predicted by rp-process calculations and the origin of A=96 isobars such as 96Ru are explored.