First experimental determination of the $^{59}$Fe($n,\gamma_0$)$^{60}$Fe reaction via Coulomb dissociation

The nucleosynthesis of $^{60}$Fe is one of the current outstanding problems in nuclear astrophysics. Observations of galactic radioactivity by $\gamma$-ray telescopes have provided a direct measurement of the $^{60}$Fe/$^{26}$Al$^{g}$ ratio dispersed across the galactic plane. As the two isotopes are produced in similar stellar environments, the ratio provides a unique constraint on current stellar models. Specifically, $^{60}$Fe is created and destroyed by neutron capture on stable iron isotopes. A recent measurement of the $^{60}$Fe(n,$\gamma$)$^{61}$Fe reaction has provided a first experimental quantification of the destruction rate. Currently, no experimental data exist for the $^{59}$Fe(n,$\gamma$)$^{60}$Fe production rate. To address this void, a Coulomb dissociation experiment has been performed at GSI to indirectly measure the ground state neutron capture cross section of $^{59}$Fe. The $^{60}$Fe beam was produced by fragmentation of a 660 AMeV primary $^{64}$Ni beam by a Be target. The $^{60}$Fe fragments were separated using the FRS and impinged on a lead target. The experimental setup provides for an event-by-event reconstruction of the four-momenta of all incoming particles and reaction products. The analysis is currently ongoing, and preliminary results will be discussed.