Measurement of the stellar \(^{58}\)Ni\((n,\gamma)^{59}\)Ni cross section with AMS

The \(^{58}\)Ni\((n,\gamma)^{59}\)Ni cross section was measured with a combination of the activation technique and accelerator mass spectrometry (AMS). The neutron activations were performed at the Karlsruhe 3.7 MV Van de Graaff accelerator using the quasi-stellar neutron spectrum at \(kT=25\) keV produced by the \(^7\)Li(\(p,n\))\(^7\)Be reaction. The subsequent AMS measurements were carried out at the 14 MV tandem accelerator of the Maier-Leibnitz-Laboratory in Garching using the Gas-filled Analyzing Magnet System (GAMS). Three individual samples were measured, yielding a Maxwellian-averaged cross section at \(kT=30\) keV of \(\langle\sigma\rangle_{30\text{keV}}\)= 30.4 (23)\(^{syst}\)(9)\(^{stat}\) mbarn. This value is slightly lower than two recently published measurements using the time-of-flight (TOF) method, but agrees within the uncertainties. Our new results also resolve the large discrepancy between older TOF measurements and our previous value.