New measurement of the capture cross section of bismuth and lead isotopes
Tain, J. L.
de Albornoz, A.C.
Goncalves, I. F.
N TOF Collaboration
All the stable lead isotopes and Bi-209 have been recently measured at n-TOF [I] (CERN) in the range from 1 eV up to I MeV, using an optimized experimental setup. A set of two homemade CA detectors with carbon-fibre canning was designed to greatly reduce the sensitivity to scattered neutrons. Surrounding elements like the sample holder and the sample exchanger have been made also of carbon fibre.The pulse-height weighting technique has been used in order to determine the (n,gamma) cross sections. Concerning this technique, special care has been taken in the treatment of several sources of error leading to a total systematic uncertainty of less than 3%.Results on the analysed Bi-209 and Pb-207 capture data and a comparison with previous experiments and evaluations are presented.