High-resolution neutron transmission and capture measurements of the nucleusPb206

Abstract

Neutron total and capture reaction cross-section measurements for $^{206}\mathrm{Pb}$ were performed at the GELINA neutron time-of-flight facility in the energy range from 1 to 620 keV. The resonance parameters corresponding to 304 excited nuclear levels in $^{207}\mathrm{Pb}$ were determined from the data using the R-matrix formalism. The results are compared to existing data. From the capture data photon strength functions have been deduced. No evidence has been found for a previously reported enhancement of the $M1$ transition strength, nor for a strong enhancement of the s-wave doorway state in the photon channel. The neutron capture cross section of $^{206}\mathrm{Pb}$ is of importance in stellar evolution calculations of the formation of the elements by neutron capture. Maxwellian-averaged neutron capture cross sections have been calculated at different stellar temperatures ranging up to 100 keV and compared with the results of previous work and evaluated data libraries.