We report on a study of the radiative decay of fission fragments populated via neutronless fission of ^{252}Cf(sf). Applying the double-energy method a perfect mass identification is achieved for these rare events. In the specific case of the ^{120}Cd/^{132}Sn cold fragmentation, we find that ^{132}Sn is produced in its ground state.
View Article and Find Full Text PDFWhen a heavy atomic nucleus splits (fission), the resulting fragments are observed to emerge spinning; this phenomenon has been a mystery in nuclear physics for over 40 years. The internal generation of typically six or seven units of angular momentum in each fragment is particularly puzzling for systems that start with zero, or almost zero, spin. There are currently no experimental observations that enable decisive discrimination between the many competing theories for the mechanism that generates the angular momentum.
View Article and Find Full Text PDFPhys Rev Lett
February 2013
A long-lived J(π) = 4(1)(+) isomer, T(1/2) = 2.2(1) ms, has been discovered at 643.4(1) keV in the weakly bound (9)(26)F nucleus.
View Article and Find Full Text PDFPhys Rev Lett
November 2012
We report on direct time-of-flight based mass measurements of 16 light neutron-rich nuclei. These include the first determination of the masses of the Borromean drip-line nuclei (19)B, (22)C, and (29)F as well as that of (34)Na. In addition, the most precise determinations to date for (23)N and (31)Ne are reported.
View Article and Find Full Text PDFWe report on the spectroscopic quadrupole moment measurement of the 7/2(1)(-) isomeric state in (16)(43)S(27) [E*=320.5(5) keV, T(1/2)=415(3) ns], using the time dependent perturbed angular distribution technique at the RIKEN RIBF facility. Our value, |Q(s)|=23(3) efm(2), is larger than that expected for a single-particle state.
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