Abstract
The radiative neutron capture cross section of has been measured at the CERN neutron time of flight installation n_TOF using the pulse height weighting technique in the resolved energy region. The measurement has been performed with an optimized setup of two C scintillation detectors, which allowed us to reduce scattered neutron backgrounds down to a negligible level. Resonance parameters and radiative kernels have been determined for 16 resonances by means of an R-matrix analysis in the neutron energy range from 3 keV to 320 keV. Good agreement with previous measurements was found at low neutron energies, whereas substantial discrepancies appear beyond 45 keV. With the present results, we obtain an -process contribution of 77±8% to the solar abundance of . This corresponds to an -process component of , which is important for deriving the U/Th ages of metal poor halo stars.
- Received 25 July 2006
DOI:https://doi.org/10.1103/PhysRevC.74.055802
©2006 American Physical Society