half of the stable nuclides heavier than iron observed in nature and is believed to result from an extremely large neutron irradiation on timescales of the order of about one second.

So far, however, the astrophysical site hosting such an r-process remains unknown. Although an $(n,\gamma$)–($\gamma,n$) equilibrium might take place in an environment with high neutron density and high temperature (in which case the r-abundance distribution remains rather insensitive to the reaction rates), more general r-process simulations require a reliable determination of the radiative neutron capture rates for all nuclei involved [@ar07]. Indeed, it should be kept in mind that even if the thermodynamic conditions of the r-process site remain unknown, the assumption of an $(n,\gamma$)–($\gamma,n$) equilibrium can only be tested if the neutron capture, $\beta$-decay and photodisintegration rates for all neutron-rich nuclei synthesized during such a process can be estimated reliably [@go96]. Furthermore, in specific sites such as the decompression of neutron star matter or the so-called cold neutrino-driven wind, neutron captures are in competition with $\beta$-decays, not with photodisintegrations, so that no $(n,\gamma$)–($\gamma,n$) equilibrium can be achieved and the final r-abundance distribution may well be sensitive to reaction rates. Finally, in any site, the final abundance distribution is 