probably have a relatively small effect. However, for neutron-rich nuclei approaching the neutron drip line, the neutron separation energy rapidly decreases and enters the energy region where the enhanced strength is observed. This work aims at investigating how such a very low-energy strength enhancement may influence the neutron-capture cross section of exotic neutron-rich nuclei. Since this upbend phenomenon has been clearly seen in Mo isotopes, the present study will focus on Mo. The Mo case is also of particular interest due to the many observational constraints that can help us to determine the full RSF; these include the resonance spacing and the average total radiative width at the neutron separation energies, photoneutron cross-section data, and the measurements by the Oslo group.

In Sect. \[sect\_exp\], we will describe the experimental results obtained by the Oslo method and the parameterizations used to model the low-energy $E1$ strength, in particular in the vicinity of the upbend structure. In Sect.  \[sect\_res\], the neutron-capture cross sections and the corresponding astrophysical rates are estimated for the Mo nuclei, as well as Fe and Cd isotopic chains. Finally, implications of these results and conclusions are discussed in Sect. \[sect\_conc\].

Experimental and theoretical description of the upbend structure 