Stringent tests of shell model calculations in fp shell nuclei Ti-46,Ti-48and Cr-50,Cr-52 from measurements of g factors and B(E2) values

Measurements of magnetic moments and lifetimes of 2(1)(+) and 4(1)(+) state s of Ti-46,Ti-48 and Cr-50,Cr-52 were performed with high accuracy via proj ectile Coulomb excitation and the technique of transient magnetic fields. T he high quality of the data allows for the first time to establish stringen t constraints on large scale shell model calculations. Whereas the global b ehavior of the data is well explained by full fp shell model calculations, distinct deviations in the g factors and B(E2) values of Ti-46,Ti-48 from t heoretical predictions can be attributed to excitations of the Ca-40 core. This suggestion is supported by recent Monte Carlo calculations which provi de evidence that Ca-48 is a better inert core.