Gamma ray spectroscopy studies in the nuclei ³⁶Ar and ³⁶Cl

Excitation energies, mean lifetimes, mixing ratios, branching ratios, angular distributions and linear polarizations have been measured for levels in ³⁶Ar and ³⁶Cl. The states were populated using the reactions ³³S( alpha ,n gamma )³⁶Ar and ³³S( alpha ,p gamma )³⁶Cl at beam energies up to 14 MeV. The decay schemes were determined with the help of a gamma-gamma coincidence experiment carried out at a beam energy of 14 MeV. New spin assignments were made for four levels in ³⁶Cl: 2518 keV, 5^-; 2810 keV, 4^-; 3102 keV, 4^-; 3723 keV, 4^-. Mean lifetimes were measured for four levels in the two nuclei using the recoil distance method. Two new levels were found in ³⁶Cl at excitation energies of 4291 keV and 5311 keV, both being candidates for high spin. The results are discussed in terms of recent shell-model calculations which reproduce very well the three new 4^- states in ³⁶Cl.