Abstract
The () cross sections of , , , , and have been measured in the energy range from 3 to 225 keV relative to the gold standard. Neutrons were produced via the () reaction and capture events were registered with the Karlsruhe 4π barium fluoride detector. The overall uncertainties are between 0.9 and 2.6%, about 5 times smaller than in previous experiments. Partial cross sections to ground and isomeric states could be experimentally identified for neutron capture on , indicating a strong population of yet-unknown isomeric states in and . This feature was confirmed by extensive GEANT simulations based on calculated capture cascades. The deduced Maxwellian-averaged () cross sections for thermal energies between and 100 keV contribute to the analysis of the s-process branchings at and and have significant consequences for the separation of the solar s- and r-process components.
4 More- Received 25 December 2005
DOI:https://doi.org/10.1103/PhysRevC.73.045807
©2006 American Physical Society