Magnetic dipole moments of Cu-58 and Cu-59 by in-source laser spectroscopy

Online measurements of the magnetic dipole moments and isotope shifts of Cu-58 and Cu-59 by the in-source laser spectroscopy method are reported. The results for the magnetic moments are mu (Cu-58) =+0.52(8) mu(N),mu(Cu-59) =+1.84(3) mu(N) and for the isotope shifts delta nu(59,65)=1.72(22) GHz and delta nu(58,65)=1.99(30) GHz in the transition from the 3d(10)4s S-2(1/2) ground state to the 3d(10)4p P-2(1/2) state in Cu I. The magnetic moment of Cu-58 is discussed in the context of the strength of the subshell closure at Ni-56, additivity rules and large-scale shell model calculations.