Isospin purity of T=1 states in the A=38 nuclei studied via lifetime measurements in K38

The Doppler Shift Attenuation Method was used to measure lifetimes for levels in {sup 38}K at excitation energies of 1698, 2404, 2830, 2996, and 3671 keV, populated using the {sup 40}Ca(d, {alpha}){sup 38}K reaction at a beam energy of 4.5 MeV. Values of 109(29), 95(22), 457(63), 130(40), and 160(50) fs, respectively, were measured and are compared with previous values obtained using different stopping powers. The matrix element for the transition between the J{sup {pi}}=2{sub T=1}{sup +} and 0{sub T=1}{sup +} states in this T{sub z}=0 nucleus is compared with the analogous transition in the other nuclei in the T=1 triplet, {sup 38}Ca (T{sub z}=-1) and {sup 38}Ar (T{sub z}=+1), and with the results of shell-model calculations.