Comparative spectroscopy with the (d, τ) reaction on even Ar isotopes

Abstract

The (d, τ) proton pick-up reactions on 36Ar and 38Ar have been studied at an incident energy of 52 MeV. Differential cross sections were measured and spectroscopic factors were extracted for transitions to 14 states of 35Cl and 13 states of 37Cl, respectively. Many new 5 2 + states and nearly the complete 1 d 5 2 strength have been observed in both nuclei. The width of the 1 d 5 2 spectral distribution is appreciably smaller for the semi-closed shell nucleus 38Ar than for 36Ar and 40Ar. The results are compared with those from the 40Ar(d, τ) reaction and proton stripping reactions on each of the three argon isotopes. Recent shell model calculations proved to be well suited to describe excitation energies as well as spectroscopic factors for the low-lying positiveparity states. Mirror relations were established for the nuclei 35Ar and 35Cl. In 37Cl we succeeded in observing a weak component of a 1p proton hole state at a separation energy of only 18 MeV.