The doubly magic nature of 56Ni can be probed by studying the properties of nuclei one nucleon removed from 56Ni. 57Cu can be modeled as a 56Ni core plus a proton in the 2p3/2 state. The nuclear magnetic dipole moment for 57Cu, carries information about the spin and angular momentum components of the nuclear state wavefunction. Therefore, the magnetic moment serves as a test of the goodness of the N=Z=28 closed shells . Atomic laser spectroscopy is one method that can be used to determine the nuclear magnetic dipole moment through the observed hyperfine spectrum. Collinear laser spectroscopy is the traditional method of choice for laser spectroscopy performed on rare isotopes. In-gas-cell laser spectroscopy is a recently developed technique that is effective for the study of isotopes with low production rates, such as 57Cu. However, the resonance linewidths observed using this technique suffer from the effect of pressure broadening. The atomic hyperfine spectrum of 57Cu was recorded at LISOL (Leuven Isotope Separator On-Line) using in-gas-cell laser spectroscopy. The magnetic moment was extracted from the hyperfine spectrum to be +2.582(7)n.m. This value agrees well with the theoretical value of +2.489 n.m. obtained from shell model calculations using the GXPF1 interaction .
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