High-spin states in43K

Abstract

The nucleus ⁴³K has been studied via the ⁴⁰Ar( alpha ,p gamma )⁴³K reaction, using solid targets of natural argon. A gamma - gamma coincidence experiment established five new levels at excitation energies of 1850, 2048, 2509, 3115 and 3139 keV. Gamma-ray angular distributions and linear polarisations were measured at an alpha-particle energy of 17.0 MeV. The analysis of these data yielded spin and parity assignments of J^pi =^7-/₂, ⁷⁺/₂, ^11-/₂ and ^15-/₂ for the levels at 738, 1510, 1850 and 3115 keV respectively. Mean lifetimes were measured for four levels using the DSAM: 1510 keV, 8.2+or-2.1 ps; 2048 keV, 2.4+or-0.8 ps; 1850 keV, 6.7+or-1.7 ps; 3115 keV, 5.0+or-1.5 ps. A lower limit of 7 ps was obtained for the lifetimes of the levels at 1207 keV and 2509 keV.