Level structure of ⁸⁷Sr from the ⁸⁶Sr(n, γ) and ⁸⁶Sr(d, p) reactions

The γ-ray spectrum emitted after thermal neutron capture in ⁸⁶Sr was studied at the ILL high flux reactor with pair- and intrinsic Ge spectrometers. 759 transitions were assigned to the reaction ⁸⁶Sr(n, γ)⁸⁷Sr and 385 of them were placed into a ⁸⁷Sr level scheme of 80 levels. This represents 90% of the observed intensity. The level energies were determined with a precision of better than 20 ppm; the neutron binding energy was determined to be 8428.16 (17)keV. In a second set of experiments high resolution particle spectra of the reactions ⁸⁶Sr(d, p)⁸⁷Sr and ⁸⁸Sr(d, t)⁸⁷Si were recorded at 20 MeV deuteron energy with the München Q3D spectrometer. These data were used to establish newly found levels and to differentiate between primary and secondary transitions in the (n, γ) data. The observed level densities and primary transition strengths are compared with statistical models.