[en] A rotation of the angular correlation of de-excitation γ-rays from ⁴⁰Ca and ⁴⁴Ca was observed in a tilted foil geometry. The signs and magnitudes of the magnetic moments of the 2₁⁺ of ⁴⁴Ca and of the 3₁^- level of ⁴⁰Ca were determined to be g = -0.28+-0.11 and g = +0.52+-0.18, respectively. This experiment provides further information regarding the polarization of deeply bound electronic configurations produced by a surface-interaction mechanism and demonstrates the feasibility of the present technique for measuring signs and magnitudes of magnetic moments of picosecond nuclear levels. (author)