Benchmark on neutron capture extracted from (d, p) reactions

Direct neutron capture reactions play an important role in nuclear astrophysics and applied physics. Since for most unstable short-lived nuclei it is not possible to measure the (n, gamma) cross sections, (d, p) reactions have been used as an alternative indirect tool. We analyze simultaneously Ca-48(d, P)Ca-49 reactions at deuteron energies of 2, 13, 19, and 56 MeV and the thermal (n, gamma) reaction at 25 meV. We include results for the ground state and the first excited state of Ca-49. From the low-energy (d, p) reaction, the neutron asymptotic normalization coefficient (ANC) is determined. Using this ANC, we extract the spectroscopic factor (SF) from the higher energy (d, p) data and the (n, gamma) data. The SF obtained through the 56-MeV (d, p) data are less accurate but consistent with those from the thermal capture. We show that to have a similar dependence on the single-particle parameters as in the (n, gamma), the (d, p) reaction should be measured at 30 MeV.