Level assignment in40K from polarization measurements (in37Cl(α,nγ)40K)

Abstract
Levels at 2291 keV, 2543 keV, 2786.6 keV and 2879 keV in 40K were studied using the 37Cl( alpha ,n gamma )40K reaction at a bombarding energy of 8.0 MeV. Angular distributions and polarizations were measured for transitions from these levels. This polarization information combined with that from earlier angular correlation measurements gives unique assignments of Jpi =7+ for the 2543 keV level and jpi =3+ for the 2786.6 keV level. The 2879 keV level is established as J=6. Combining the polarization results with those of a single-particle transfer experiment, Jpi =3- is favoured for the 2291 keV level. Simple shell- model calculations aimed at interpreting the new data are reported.